diff --git a/app/src/main/java/org/linphone/ui/main/settings/fragment/AccountProfileFragment.kt b/app/src/main/java/org/linphone/ui/main/settings/fragment/AccountProfileFragment.kt
index 7c64b2e6d..d9cd50e96 100644
--- a/app/src/main/java/org/linphone/ui/main/settings/fragment/AccountProfileFragment.kt
+++ b/app/src/main/java/org/linphone/ui/main/settings/fragment/AccountProfileFragment.kt
@@ -103,7 +103,7 @@ class AccountProfileFragment : GenericFragment() {
         }
 
         binding.setPrefixTooltipClickListener {
-            // TODO
+            showHelpPopup()
         }
 
         binding.setChangeModeClickListener {
@@ -195,4 +195,10 @@ class AccountProfileFragment : GenericFragment() {
         binding.prefix.onItemSelectedListener = dropdownListener
         binding.prefix.setSelection(dialPlanIndex)
     }
+
+    @UiThread
+    private fun showHelpPopup() {
+        val dialog = DialogUtils.getAccountInternationalPrefixHelpDialog(requireActivity())
+        dialog.show()
+    }
 }
diff --git a/app/src/main/java/org/linphone/utils/DialogUtils.kt b/app/src/main/java/org/linphone/utils/DialogUtils.kt
index 80a108082..f8b21a28d 100644
--- a/app/src/main/java/org/linphone/utils/DialogUtils.kt
+++ b/app/src/main/java/org/linphone/utils/DialogUtils.kt
@@ -39,6 +39,7 @@ import org.linphone.databinding.DialogConfirmZrtpSasBinding
 import org.linphone.databinding.DialogContactConfirmTrustCallBinding
 import org.linphone.databinding.DialogContactTrustProcessBinding
 import org.linphone.databinding.DialogDeleteContactBinding
+import org.linphone.databinding.DialogManageAccountInternationalPrefixHelpBinding
 import org.linphone.databinding.DialogPickNumberOrAddressBinding
 import org.linphone.databinding.DialogRemoveAccountBinding
 import org.linphone.databinding.DialogRemoveAllCallLogsBinding
@@ -86,6 +87,23 @@ class DialogUtils {
             return getDialog(context, binding)
         }
 
+        @UiThread
+        fun getAccountInternationalPrefixHelpDialog(context: Context): Dialog {
+            val binding: DialogManageAccountInternationalPrefixHelpBinding = DataBindingUtil.inflate(
+                LayoutInflater.from(context),
+                R.layout.dialog_manage_account_international_prefix_help,
+                null,
+                false
+            )
+            val dialog = getDialog(context, binding)
+
+            binding.setDismissClickListener {
+                dialog.dismiss()
+            }
+
+            return dialog
+        }
+
         @UiThread
         fun getAccountModeExplanationDialog(
             context: Context,
diff --git a/app/src/main/res/layout/dialog_manage_account_international_prefix_help.xml b/app/src/main/res/layout/dialog_manage_account_international_prefix_help.xml
new file mode 100644
index 000000000..65c56d243
--- /dev/null
+++ b/app/src/main/res/layout/dialog_manage_account_international_prefix_help.xml
@@ -0,0 +1,87 @@
+<?xml version="1.0" encoding="utf-8"?>
+<layout
+    xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto">
+
+    <data>
+        <import type="android.view.View" />
+        <variable
+            name="dismissClickListener"
+            type="View.OnClickListener" />
+    </data>
+
+    <androidx.constraintlayout.widget.ConstraintLayout
+        android:onClick="@{dismissClickListener}"
+        android:layout_width="match_parent"
+        android:layout_height="match_parent">
+
+        <ImageView
+            android:id="@+id/dialog_background"
+            android:layout_width="0dp"
+            android:layout_height="0dp"
+            android:layout_marginStart="12dp"
+            android:layout_marginEnd="12dp"
+            android:layout_marginBottom="2dp"
+            android:src="@drawable/shape_dialog_background"
+            app:layout_constraintWidth_max="@dimen/dialog_max_width"
+            app:layout_constraintBottom_toBottomOf="@id/anchor"
+            app:layout_constraintEnd_toEndOf="parent"
+            app:layout_constraintStart_toStartOf="parent"
+            app:layout_constraintTop_toTopOf="@id/title" />
+
+        <androidx.appcompat.widget.AppCompatTextView
+            style="@style/section_header_style"
+            android:id="@+id/title"
+            android:layout_width="0dp"
+            android:layout_height="wrap_content"
+            android:layout_marginStart="15dp"
+            android:paddingTop="@dimen/dialog_top_bottom_margin"
+            android:text="@string/dialog_account_international_prefix_help_title"
+            app:layout_constraintVertical_chainStyle="packed"
+            app:layout_constraintBottom_toTopOf="@id/message"
+            app:layout_constraintStart_toStartOf="@id/dialog_background"
+            app:layout_constraintEnd_toEndOf="@id/dialog_background"
+            app:layout_constraintTop_toTopOf="parent" />
+
+        <androidx.appcompat.widget.AppCompatTextView
+            style="@style/default_text_style"
+            android:id="@+id/message"
+            android:layout_width="0dp"
+            android:layout_height="wrap_content"
+            android:layout_marginStart="15dp"
+            android:layout_marginEnd="15dp"
+            android:layout_marginTop="10dp"
+            android:text="@string/dialog_account_international_prefix_help_message"
+            android:textSize="14sp"
+            app:layout_constraintBottom_toTopOf="@id/confirm"
+            app:layout_constraintStart_toStartOf="@id/dialog_background"
+            app:layout_constraintEnd_toEndOf="@id/dialog_background"
+            app:layout_constraintTop_toBottomOf="@id/title" />
+
+        <androidx.appcompat.widget.AppCompatTextView
+            android:onClick="@{dismissClickListener}"
+            style="@style/primary_button_label_style"
+            android:id="@+id/confirm"
+            android:layout_width="0dp"
+            android:layout_height="wrap_content"
+            android:layout_marginTop="32dp"
+            android:layout_marginStart="15dp"
+            android:layout_marginEnd="15dp"
+            android:text="@string/dialog_ok"
+            app:layout_constraintStart_toStartOf="@id/dialog_background"
+            app:layout_constraintEnd_toEndOf="@id/dialog_background"
+            app:layout_constraintTop_toBottomOf="@id/message"
+            app:layout_constraintBottom_toTopOf="@id/anchor"/>
+
+        <View
+            android:id="@+id/anchor"
+            android:layout_width="wrap_content"
+            android:layout_height="@dimen/dialog_top_bottom_margin"
+            app:layout_constraintTop_toBottomOf="@id/confirm"
+            app:layout_constraintStart_toStartOf="@id/dialog_background"
+            app:layout_constraintEnd_toEndOf="@id/dialog_background"
+            app:layout_constraintBottom_toBottomOf="parent"/>
+
+    </androidx.constraintlayout.widget.ConstraintLayout>
+
+</layout>
\ No newline at end of file
diff --git a/app/src/main/res/values/strings.xml b/app/src/main/res/values/strings.xml
index 97d1af6cf..d48572d2a 100644
--- a/app/src/main/res/values/strings.xml
+++ b/app/src/main/res/values/strings.xml
@@ -96,6 +96,8 @@
     <string name="dialog_remove_account_message">You can reconnect at any time by clicking “Add an account”. However, all data on this phone will be deleted.</string>
     <string name="dialog_update_available_title">Update available</string>
     <string name="dialog_update_available_message">A new version %s is available. Do you want to update?</string>
+    <string name="dialog_account_international_prefix_help_title">Why do we need it?</string>
+    <string name="dialog_account_international_prefix_help_message">Blah blah blah</string>
 
     <string name="toast_assistant_qr_code_invalid">Invalid QR code!</string>
     <string name="toast_sip_address_copied_to_clipboard">SIP address copied into clipboard</string>