diff --git a/dotnet/targets/Xamarin.Shared.Sdk.props b/dotnet/targets/Xamarin.Shared.Sdk.props
index 29788097368..99b9d4a98d3 100644
--- a/dotnet/targets/Xamarin.Shared.Sdk.props
+++ b/dotnet/targets/Xamarin.Shared.Sdk.props
@@ -137,6 +137,12 @@
 
 	</PropertyGroup>
 
+	<!-- Set the default RuntimeIdentifier when publishing -->
+	<PropertyGroup Condition="'$(PublishRuntimeIdentifier)' == ''">
+		<PublishRuntimeIdentifier Condition="'$(_PlatformName)' == 'iOS'">ios-arm64</PublishRuntimeIdentifier>
+		<PublishRuntimeIdentifier Condition="'$(_PlatformName)' == 'tvOS'">tvos-arm64</PublishRuntimeIdentifier>
+	</PropertyGroup>
+
 	<!-- Now that we know the runtime identifier, we can determine if we're building for a simulator -->
 	<PropertyGroup>
 		<_SdkIsSimulator Condition="$(RuntimeIdentifier.Contains('simulator')) Or $(RuntimeIdentifiers.Contains('simulator'))">true</_SdkIsSimulator>
diff --git a/tests/xharness/Jenkins/TestVariationsFactory.cs b/tests/xharness/Jenkins/TestVariationsFactory.cs
index 5898ed462cd..50f4c27c94b 100644
--- a/tests/xharness/Jenkins/TestVariationsFactory.cs
+++ b/tests/xharness/Jenkins/TestVariationsFactory.cs
@@ -229,6 +229,8 @@ public IEnumerable<T> CreateTestVariations<T> (IEnumerable<T> tests, Func<MSBuil
 						if (publishaot) {
 							clone.Xml.SetProperty ("PublishAot", "true", last: false);
 							clone.Xml.SetProperty ("_IsPublishing", "true", last: false); // quack like "dotnet publish", otherwise PublishAot=true has no effect.
+							if (!string.IsNullOrEmpty (runtime_identifer))
+								clone.Xml.SetProperty ("PublishRuntimeIdentifier", runtime_identifer);
 						}
 						if (!string.IsNullOrEmpty (test_variation)) {
 							clone.Xml.SetProperty ("TestVariation", test_variation);