diff --git a/ui/build/rbe.go b/ui/build/rbe.go
index 3e558f7..82fc15f 100644
--- a/ui/build/rbe.go
+++ b/ui/build/rbe.go
@@ -19,6 +19,7 @@
 	"os"
 	"path/filepath"
 	"runtime"
+	"strings"
 
 	"android/soong/ui/metrics"
 )
@@ -126,6 +127,34 @@
 	}
 }
 
+func prodCredsAuthType(config Config) bool {
+	authVar, val := config.rbeAuth()
+	if strings.Contains(authVar, "use_google_prod_creds") && val != "" && val != "false" {
+		return true
+	}
+	return false
+}
+
+// Check whether proper auth exists for RBE builds run within a
+// Google dev environment.
+func CheckProdCreds(ctx Context, config Config) {
+	if !config.IsGooglerEnvironment() {
+		return
+	}
+	if !config.StubbyExists() && prodCredsAuthType(config) {
+		fmt.Fprintln(ctx.Writer, "")
+		fmt.Fprintln(ctx.Writer, fmt.Sprintf("\033[33mWARNING: %q binary not found in $PATH, follow go/build-fast#opting-out-of-loas-credentials instead for authenticating with RBE.\033[0m", "stubby"))
+		fmt.Fprintln(ctx.Writer, "")
+		return
+	}
+	if config.GoogleProdCredsExist() {
+		return
+	}
+	fmt.Fprintln(ctx.Writer, "")
+	fmt.Fprintln(ctx.Writer, "\033[33mWARNING: Missing LOAS credentials, please run `gcert`. This will result in failing builds in the future, see go/rbe-android-default-announcement.\033[0m")
+	fmt.Fprintln(ctx.Writer, "")
+}
+
 // DumpRBEMetrics creates a metrics protobuf file containing RBE related metrics.
 // The protobuf file is created if RBE is enabled and the proxy service has
 // started. The proxy service is shutdown in order to dump the RBE metrics to the