diff --git a/pungi/scripts/pungi_koji.py b/pungi/scripts/pungi_koji.py
index b63ddd6e..c262e775 100644
--- a/pungi/scripts/pungi_koji.py
+++ b/pungi/scripts/pungi_koji.py
@@ -272,7 +272,7 @@ def main():
         logger, opts.skip_phase + conf.get("skip_phases", []), opts.just_phase
     ):
         sys.exit(1)
-    errors, warnings = pungi.checks.validate(conf)
+    errors, warnings = pungi.checks.validate(conf, offline=True)
 
     if not opts.quiet:
         # TODO: workaround for config files containing skip_phase = productimg
@@ -328,6 +328,13 @@ def main():
         logger=logger,
         notifier=notifier,
     )
+    errors, warnings = pungi.checks.validate(conf, offline=False)
+    if errors:
+        for error in errors:
+            logger.error("Config validation failed with the error: %s" % error)
+        fail_to_start("Config validation failed", errors=errors)
+        sys.exit(1)
+
     notifier.compose = compose
     COMPOSE = compose
     try:
diff --git a/pungi/util.py b/pungi/util.py
index da5e82f2..c6a40d4d 100644
--- a/pungi/util.py
+++ b/pungi/util.py
@@ -288,8 +288,12 @@ def resolve_git_ref(repourl, ref):
     if re.match(r"^[a-f0-9]{40}$", ref):
         # This looks like a commit ID already.
         return ref
-
-    _, output = git_ls_remote(repourl, ref)
+    try:
+        _, output = git_ls_remote(repourl, ref)
+    except RuntimeError as e:
+        raise GitUrlResolveError(
+            "ref does not exist in remote repo %s with the error %s" % (repourl, e)
+        )
 
     lines = []
     for line in output.split("\n"):