diff --git a/app/src/main/java/com/nextcloud/talk/activities/CallActivity.kt b/app/src/main/java/com/nextcloud/talk/activities/CallActivity.kt
index e8472e973..7a4fecb25 100644
--- a/app/src/main/java/com/nextcloud/talk/activities/CallActivity.kt
+++ b/app/src/main/java/com/nextcloud/talk/activities/CallActivity.kt
@@ -1590,6 +1590,8 @@ class CallActivity : CallBaseActivity() {
                         hasMCU = false
 
                         messageSender = MessageSenderNoMcu(
+                            signalingMessageSender,
+                            callParticipants.keys,
                             peerConnectionWrapperList
                         )
 
@@ -1895,11 +1897,15 @@ class CallActivity : CallBaseActivity() {
 
             if (hasMCU) {
                 messageSender = MessageSenderMcu(
+                    signalingMessageSender,
+                    callParticipants.keys,
                     peerConnectionWrapperList,
                     webSocketClient!!.sessionId
                 )
             } else {
                 messageSender = MessageSenderNoMcu(
+                    signalingMessageSender,
+                    callParticipants.keys,
                     peerConnectionWrapperList
                 )
             }
@@ -1934,11 +1940,15 @@ class CallActivity : CallBaseActivity() {
 
                     if (hasMCU) {
                         messageSender = MessageSenderMcu(
+                            signalingMessageSender,
+                            callParticipants.keys,
                             peerConnectionWrapperList,
                             webSocketClient!!.sessionId
                         )
                     } else {
                         messageSender = MessageSenderNoMcu(
+                            signalingMessageSender,
+                            callParticipants.keys,
                             peerConnectionWrapperList
                         )
                     }
diff --git a/app/src/main/java/com/nextcloud/talk/call/MessageSender.java b/app/src/main/java/com/nextcloud/talk/call/MessageSender.java
index a868fc6b8..dd3eb149a 100644
--- a/app/src/main/java/com/nextcloud/talk/call/MessageSender.java
+++ b/app/src/main/java/com/nextcloud/talk/call/MessageSender.java
@@ -7,16 +7,22 @@
 package com.nextcloud.talk.call;
 
 import com.nextcloud.talk.models.json.signaling.DataChannelMessage;
+import com.nextcloud.talk.models.json.signaling.NCSignalingMessage;
+import com.nextcloud.talk.signaling.SignalingMessageSender;
 import com.nextcloud.talk.webrtc.PeerConnectionWrapper;
 
 import java.util.List;
+import java.util.Set;
 
 /**
  * Helper class to send messages to participants in a call.
  * <p>
  * A specific subclass has to be created depending on whether an MCU is being used or not.
  * <p>
- * Note that, unlike signaling messages, data channel messages require a peer connection. Therefore data channel
+ * Note that recipients of signaling messages are not validated, so no error will be triggered if trying to send a
+ * message to a participant with a session ID that does not exist or is not in the call.
+ * <p>
+ * Also note that, unlike signaling messages, data channel messages require a peer connection. Therefore data channel
  * messages may not be received by a participant if there is no peer connection with that participant (for example, if
  * neither the local and remote participants have publishing rights). Moreover, data channel messages are expected to
  * be received only on peer connections with type "video", so data channel messages will not be sent on other peer
@@ -24,9 +30,17 @@ import java.util.List;
  */
 public abstract class MessageSender {
 
+    private final SignalingMessageSender signalingMessageSender;
+
+    private final Set<String> callParticipantSessionIds;
+
     protected final List<PeerConnectionWrapper> peerConnectionWrappers;
 
-    public MessageSender(List<PeerConnectionWrapper> peerConnectionWrappers) {
+    public MessageSender(SignalingMessageSender signalingMessageSender,
+                         Set<String> callParticipantSessionIds,
+                         List<PeerConnectionWrapper> peerConnectionWrappers) {
+        this.signalingMessageSender = signalingMessageSender;
+        this.callParticipantSessionIds = callParticipantSessionIds;
         this.peerConnectionWrappers = peerConnectionWrappers;
     }
 
@@ -37,6 +51,35 @@ public abstract class MessageSender {
      */
     public abstract void sendToAll(DataChannelMessage dataChannelMessage);
 
+    /**
+     * Sends the given signaling message to the given session ID.
+     * <p>
+     * Note that the signaling message will be modified to set the recipient in the "to" field.
+     *
+     * @param ncSignalingMessage the message to send
+     * @param sessionId the signaling session ID of the participant to send the message to
+     */
+    public void send(NCSignalingMessage ncSignalingMessage, String sessionId) {
+        ncSignalingMessage.setTo(sessionId);
+
+        signalingMessageSender.send(ncSignalingMessage);
+    }
+
+    /**
+     * Sends the given signaling message to all the participants in the call.
+     * <p>
+     * Note that the signaling message will be modified to set each of the recipients in the "to" field.
+     *
+     * @param ncSignalingMessage the message to send
+     */
+    public void sendToAll(NCSignalingMessage ncSignalingMessage) {
+        for (String sessionId: callParticipantSessionIds) {
+            ncSignalingMessage.setTo(sessionId);
+
+            signalingMessageSender.send(ncSignalingMessage);
+        }
+    }
+
     protected PeerConnectionWrapper getPeerConnectionWrapper(String sessionId) {
         for (PeerConnectionWrapper peerConnectionWrapper: peerConnectionWrappers) {
             if (peerConnectionWrapper.getSessionId().equals(sessionId)
diff --git a/app/src/main/java/com/nextcloud/talk/call/MessageSenderMcu.java b/app/src/main/java/com/nextcloud/talk/call/MessageSenderMcu.java
index f3278fe4c..0b7d3eaee 100644
--- a/app/src/main/java/com/nextcloud/talk/call/MessageSenderMcu.java
+++ b/app/src/main/java/com/nextcloud/talk/call/MessageSenderMcu.java
@@ -7,9 +7,11 @@
 package com.nextcloud.talk.call;
 
 import com.nextcloud.talk.models.json.signaling.DataChannelMessage;
+import com.nextcloud.talk.signaling.SignalingMessageSender;
 import com.nextcloud.talk.webrtc.PeerConnectionWrapper;
 
 import java.util.List;
+import java.util.Set;
 
 /**
  * Helper class to send messages to participants in a call when an MCU is used.
@@ -21,9 +23,11 @@ public class MessageSenderMcu extends MessageSender {
 
     private final String ownSessionId;
 
-    public MessageSenderMcu(List<PeerConnectionWrapper> peerConnectionWrappers,
+    public MessageSenderMcu(SignalingMessageSender signalingMessageSender,
+                            Set<String> callParticipantSessionIds,
+                            List<PeerConnectionWrapper> peerConnectionWrappers,
                             String ownSessionId) {
-        super(peerConnectionWrappers);
+        super(signalingMessageSender, callParticipantSessionIds, peerConnectionWrappers);
 
         this.ownSessionId = ownSessionId;
     }
diff --git a/app/src/main/java/com/nextcloud/talk/call/MessageSenderNoMcu.java b/app/src/main/java/com/nextcloud/talk/call/MessageSenderNoMcu.java
index b5b903503..d6c837bb7 100644
--- a/app/src/main/java/com/nextcloud/talk/call/MessageSenderNoMcu.java
+++ b/app/src/main/java/com/nextcloud/talk/call/MessageSenderNoMcu.java
@@ -7,17 +7,21 @@
 package com.nextcloud.talk.call;
 
 import com.nextcloud.talk.models.json.signaling.DataChannelMessage;
+import com.nextcloud.talk.signaling.SignalingMessageSender;
 import com.nextcloud.talk.webrtc.PeerConnectionWrapper;
 
 import java.util.List;
+import java.util.Set;
 
 /**
  * Helper class to send messages to participants in a call when an MCU is not used.
  */
 public class MessageSenderNoMcu extends MessageSender {
 
-    public MessageSenderNoMcu(List<PeerConnectionWrapper> peerConnectionWrappers) {
-        super(peerConnectionWrappers);
+    public MessageSenderNoMcu(SignalingMessageSender signalingMessageSender,
+                              Set<String> callParticipantSessionIds,
+                              List<PeerConnectionWrapper> peerConnectionWrappers) {
+        super(signalingMessageSender, callParticipantSessionIds, peerConnectionWrappers);
     }
 
     /**
diff --git a/app/src/test/java/com/nextcloud/talk/call/MessageSenderMcuTest.kt b/app/src/test/java/com/nextcloud/talk/call/MessageSenderMcuTest.kt
index 49ca9e864..9fd8d6289 100644
--- a/app/src/test/java/com/nextcloud/talk/call/MessageSenderMcuTest.kt
+++ b/app/src/test/java/com/nextcloud/talk/call/MessageSenderMcuTest.kt
@@ -7,6 +7,7 @@
 package com.nextcloud.talk.call
 
 import com.nextcloud.talk.models.json.signaling.DataChannelMessage
+import com.nextcloud.talk.signaling.SignalingMessageSender
 import com.nextcloud.talk.webrtc.PeerConnectionWrapper
 import org.junit.Before
 import org.junit.Test
@@ -27,6 +28,10 @@ class MessageSenderMcuTest {
 
     @Before
     fun setUp() {
+        val signalingMessageSender = Mockito.mock(SignalingMessageSender::class.java)
+
+        val callParticipants = HashMap<String, CallParticipant>()
+
         peerConnectionWrappers = ArrayList()
 
         peerConnectionWrapper1 = Mockito.mock(PeerConnectionWrapper::class.java)
@@ -59,7 +64,12 @@ class MessageSenderMcuTest {
         Mockito.`when`(ownPeerConnectionWrapperScreen!!.videoStreamType).thenReturn("screen")
         peerConnectionWrappers!!.add(ownPeerConnectionWrapperScreen)
 
-        messageSender = MessageSenderMcu(peerConnectionWrappers, "ownSessionId")
+        messageSender = MessageSenderMcu(
+            signalingMessageSender,
+            callParticipants.keys,
+            peerConnectionWrappers,
+            "ownSessionId"
+        )
     }
 
     @Test
diff --git a/app/src/test/java/com/nextcloud/talk/call/MessageSenderNoMcuTest.kt b/app/src/test/java/com/nextcloud/talk/call/MessageSenderNoMcuTest.kt
index 6784bcef3..303108ed9 100644
--- a/app/src/test/java/com/nextcloud/talk/call/MessageSenderNoMcuTest.kt
+++ b/app/src/test/java/com/nextcloud/talk/call/MessageSenderNoMcuTest.kt
@@ -7,6 +7,7 @@
 package com.nextcloud.talk.call
 
 import com.nextcloud.talk.models.json.signaling.DataChannelMessage
+import com.nextcloud.talk.signaling.SignalingMessageSender
 import com.nextcloud.talk.webrtc.PeerConnectionWrapper
 import org.junit.Before
 import org.junit.Test
@@ -25,6 +26,10 @@ class MessageSenderNoMcuTest {
 
     @Before
     fun setUp() {
+        val signalingMessageSender = Mockito.mock(SignalingMessageSender::class.java)
+
+        val callParticipants = HashMap<String, CallParticipant>()
+
         peerConnectionWrappers = ArrayList()
 
         peerConnectionWrapper1 = Mockito.mock(PeerConnectionWrapper::class.java)
@@ -47,7 +52,7 @@ class MessageSenderNoMcuTest {
         Mockito.`when`(peerConnectionWrapper4Screen!!.videoStreamType).thenReturn("screen")
         peerConnectionWrappers!!.add(peerConnectionWrapper4Screen)
 
-        messageSender = MessageSenderNoMcu(peerConnectionWrappers)
+        messageSender = MessageSenderNoMcu(signalingMessageSender, callParticipants.keys, peerConnectionWrappers)
     }
 
     @Test
diff --git a/app/src/test/java/com/nextcloud/talk/call/MessageSenderTest.kt b/app/src/test/java/com/nextcloud/talk/call/MessageSenderTest.kt
new file mode 100644
index 000000000..46915ef40
--- /dev/null
+++ b/app/src/test/java/com/nextcloud/talk/call/MessageSenderTest.kt
@@ -0,0 +1,134 @@
+/*
+ * Nextcloud Talk - Android Client
+ *
+ * SPDX-FileCopyrightText: 2024 Daniel Calviño Sánchez <danxuliu@gmail.com>
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ */
+package com.nextcloud.talk.call
+
+import com.nextcloud.talk.models.json.signaling.DataChannelMessage
+import com.nextcloud.talk.models.json.signaling.NCSignalingMessage
+import com.nextcloud.talk.signaling.SignalingMessageSender
+import com.nextcloud.talk.webrtc.PeerConnectionWrapper
+import org.junit.Assert.assertTrue
+import org.junit.Before
+import org.junit.Test
+import org.mockito.Mockito
+import org.mockito.Mockito.any
+import org.mockito.Mockito.doAnswer
+import org.mockito.Mockito.times
+import org.mockito.invocation.InvocationOnMock
+
+class MessageSenderTest {
+
+    private class MessageSender(
+        signalingMessageSender: SignalingMessageSender?,
+        callParticipantSessionIds: Set<String>?,
+        peerConnectionWrappers: List<PeerConnectionWrapper>?
+    ) : com.nextcloud.talk.call.MessageSender(
+        signalingMessageSender,
+        callParticipantSessionIds,
+        peerConnectionWrappers
+    ) {
+
+        override fun sendToAll(dataChannelMessage: DataChannelMessage?) {
+            // Not used in base class tests
+        }
+    }
+
+    private var signalingMessageSender: SignalingMessageSender? = null
+
+    private var callParticipants: MutableMap<String, CallParticipant>? = null
+
+    private var messageSender: MessageSender? = null
+
+    @Before
+    fun setUp() {
+        signalingMessageSender = Mockito.mock(SignalingMessageSender::class.java)
+
+        callParticipants = HashMap()
+
+        val callParticipant1: CallParticipant = Mockito.mock(CallParticipant::class.java)
+        callParticipants!!["theSessionId1"] = callParticipant1
+
+        val callParticipant2: CallParticipant = Mockito.mock(CallParticipant::class.java)
+        callParticipants!!["theSessionId2"] = callParticipant2
+
+        val callParticipant3: CallParticipant = Mockito.mock(CallParticipant::class.java)
+        callParticipants!!["theSessionId3"] = callParticipant3
+
+        val callParticipant4: CallParticipant = Mockito.mock(CallParticipant::class.java)
+        callParticipants!!["theSessionId4"] = callParticipant4
+
+        val peerConnectionWrappers = ArrayList<PeerConnectionWrapper>()
+
+        messageSender = MessageSender(signalingMessageSender, callParticipants!!.keys, peerConnectionWrappers)
+    }
+
+    @Test
+    fun testSendSignalingMessage() {
+        val message: NCSignalingMessage = Mockito.mock(NCSignalingMessage::class.java)
+        messageSender!!.send(message, "theSessionId2")
+
+        Mockito.verify(message).to = "theSessionId2"
+        Mockito.verify(signalingMessageSender!!).send(message)
+    }
+
+    @Test
+    fun testSendSignalingMessageIfUnknownSessionId() {
+        val message: NCSignalingMessage = Mockito.mock(NCSignalingMessage::class.java)
+        messageSender!!.send(message, "unknownSessionId")
+
+        Mockito.verify(message).to = "unknownSessionId"
+        Mockito.verify(signalingMessageSender!!).send(message)
+    }
+
+    @Test
+    fun testSendSignalingMessageToAll() {
+        val sentTo: MutableList<String?> = ArrayList()
+        doAnswer { invocation: InvocationOnMock ->
+            val arguments = invocation.arguments
+            val message = (arguments[0] as NCSignalingMessage)
+
+            sentTo.add(message.to)
+            null
+        }.`when`(signalingMessageSender!!).send(any())
+
+        val message = NCSignalingMessage()
+        messageSender!!.sendToAll(message)
+
+        assertTrue(sentTo.contains("theSessionId1"))
+        assertTrue(sentTo.contains("theSessionId2"))
+        assertTrue(sentTo.contains("theSessionId3"))
+        assertTrue(sentTo.contains("theSessionId4"))
+        Mockito.verify(signalingMessageSender!!, times(4)).send(message)
+        Mockito.verifyNoMoreInteractions(signalingMessageSender)
+    }
+
+    @Test
+    fun testSendSignalingMessageToAllWhenParticipantsWereUpdated() {
+        val callParticipant5: CallParticipant = Mockito.mock(CallParticipant::class.java)
+        callParticipants!!["theSessionId5"] = callParticipant5
+
+        callParticipants!!.remove("theSessionId2")
+        callParticipants!!.remove("theSessionId3")
+
+        val sentTo: MutableList<String?> = ArrayList()
+        doAnswer { invocation: InvocationOnMock ->
+            val arguments = invocation.arguments
+            val message = (arguments[0] as NCSignalingMessage)
+
+            sentTo.add(message.to)
+            null
+        }.`when`(signalingMessageSender!!).send(any())
+
+        val message = NCSignalingMessage()
+        messageSender!!.sendToAll(message)
+
+        assertTrue(sentTo.contains("theSessionId1"))
+        assertTrue(sentTo.contains("theSessionId4"))
+        assertTrue(sentTo.contains("theSessionId5"))
+        Mockito.verify(signalingMessageSender!!, times(3)).send(message)
+        Mockito.verifyNoMoreInteractions(signalingMessageSender)
+    }
+}