diff --git a/project.py b/project.py
index 83dcf551..2248a7ef 100644
--- a/project.py
+++ b/project.py
@@ -1880,6 +1880,8 @@ class Project(object):
         result.extend(project.GetDerivedSubprojects())
         continue
 
+      if url.startswith('..'):
+        url = urllib.parse.urljoin("%s/" % self.remote.url, url)
       remote = RemoteSpec(self.remote.name,
                           url=url,
                           pushUrl=self.remote.pushUrl,