diff --git a/ArmPlatformPkg/Library/ArmPlatformLibNull/ArmPlatformLibNull.c b/ArmPlatformPkg/Library/ArmPlatformLibNull/ArmPlatformLibNull.c
index 0cc1e4a03c..f80a276a04 100644
--- a/ArmPlatformPkg/Library/ArmPlatformLibNull/ArmPlatformLibNull.c
+++ b/ArmPlatformPkg/Library/ArmPlatformLibNull/ArmPlatformLibNull.c
@@ -135,14 +135,12 @@ PrePeiCoreGetMpCoreInfo (
   }
 }
 
-// Needs to be declared in the file. Otherwise gArmMpCoreInfoPpiGuid is undefined in the contect of PrePeiCore
-EFI_GUID mArmMpCoreInfoPpiGuid = ARM_MP_CORE_INFO_PPI_GUID;
 ARM_MP_CORE_INFO_PPI mMpCoreInfoPpi = { PrePeiCoreGetMpCoreInfo };
 
 EFI_PEI_PPI_DESCRIPTOR      gPlatformPpiTable[] = {
   {
     EFI_PEI_PPI_DESCRIPTOR_PPI,
-    &mArmMpCoreInfoPpiGuid,
+    &gArmMpCoreInfoPpiGuid,
     &mMpCoreInfoPpi
   }
 };
diff --git a/ArmPlatformPkg/Library/ArmPlatformLibNull/ArmPlatformLibNull.inf b/ArmPlatformPkg/Library/ArmPlatformLibNull/ArmPlatformLibNull.inf
index 4517ad5102..97b2a4b6e4 100644
--- a/ArmPlatformPkg/Library/ArmPlatformLibNull/ArmPlatformLibNull.inf
+++ b/ArmPlatformPkg/Library/ArmPlatformLibNull/ArmPlatformLibNull.inf
@@ -46,3 +46,6 @@
 
   gArmTokenSpaceGuid.PcdArmPrimaryCoreMask
   gArmTokenSpaceGuid.PcdArmPrimaryCore
+
+[Ppis]
+  gArmMpCoreInfoPpiGuid