diff --git a/build/Base.props b/build/Base.props
index c2fc11c94b..2d50a7eae0 100644
--- a/build/Base.props
+++ b/build/Base.props
@@ -1,5 +1,6 @@
 <Project DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
-  <ItemGroup Condition="'$(TargetFramework)' != 'net6'">
+  <!-- '!NET6_0_OR_GREATER' equivalent -->
+  <ItemGroup Condition="!('$(TargetFrameworkIdentifier)' == '.NETCoreApp' AND $([MSBuild]::VersionGreaterThanOrEquals($(TargetFrameworkVersion), '6.0')))">
     <PackageReference Include="System.ValueTuple" Version="4.5.0" />
     <PackageReference Include="Microsoft.Bcl.AsyncInterfaces" Version="6.0.0" />
     <PackageReference Include="System.Threading.Tasks.Extensions" Version="4.5.4" />
diff --git a/build/System.Memory.props b/build/System.Memory.props
index a413e18927..35a87a3a2f 100644
--- a/build/System.Memory.props
+++ b/build/System.Memory.props
@@ -1,5 +1,6 @@
 <Project DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
-  <ItemGroup Condition="'$(TargetFramework)' != 'net6'">
+  <!-- '!NET6_0_OR_GREATER' equivalent -->
+  <ItemGroup Condition="!('$(TargetFrameworkIdentifier)' == '.NETCoreApp' AND $([MSBuild]::VersionGreaterThanOrEquals($(TargetFrameworkVersion), '6.0')))">
     <PackageReference Include="System.Memory" Version="4.5.3" />
   </ItemGroup>
 </Project>