diff --git a/Command/MigrationGenerateDiffCommand.php b/Command/MigrationGenerateDiffCommand.php
index 6ff16cf..cfeaa13 100644
--- a/Command/MigrationGenerateDiffCommand.php
+++ b/Command/MigrationGenerateDiffCommand.php
@@ -47,8 +47,16 @@ EOT
      */
     protected function execute(InputInterface $input, OutputInterface $output)
     {
-        $this->callPhing('diff');
-
-        $this->writeSummary($output, 'propel-sql-diff');
+        if (true === $this->callPhing('diff')) {
+            $this->writeSummary($output, 'propel-sql-diff');
+        } elseif ( strpos( $this->buffer, 'Uncommitted migrations have been found' ) ) {
+            $this->writeSection($output, array(
+                '[Propel] Error',
+                '',
+                'Uncommitted migrations have been found. You should either execute or delete them before rerunning the propel:migration:generate-diff command.'
+            ), 'fg=white;bg=red');
+        } else {
+            $this->writeTaskError($output, 'propel-sql-diff');
+        }
     }
 }