diff --git a/meta/classes-recipe/populate_sdk_ext.bbclass b/meta/classes-recipe/populate_sdk_ext.bbclass
index 09d5e2aeb6..e76ef60720 100644
--- a/meta/classes-recipe/populate_sdk_ext.bbclass
+++ b/meta/classes-recipe/populate_sdk_ext.bbclass
@@ -732,7 +732,7 @@ sdk_ext_postinst() {
 		echo "# Save and reset OECORE_NATIVE_SYSROOT as buildtools may change it" >> $env_setup_script
 		echo "SAVED=\"\$OECORE_NATIVE_SYSROOT\"" >> $env_setup_script
 		echo ". $target_sdk_dir/buildtools/environment-setup*" >> $env_setup_script
-		echo "OECORE_NATIVE_SYSROOT=\"\$SAVED\"" >> $env_setup_script
+		echo "export OECORE_NATIVE_SYSROOT=\"\$SAVED\"" >> $env_setup_script
 	fi
 
 	# Allow bitbake environment setup to be ran as part of this sdk.