diff --git a/Signal/src/AppDelegate.m b/Signal/src/AppDelegate.m
index fb3540edb..026d3d9da 100644
--- a/Signal/src/AppDelegate.m
+++ b/Signal/src/AppDelegate.m
@@ -265,6 +265,12 @@ static NSString *const kURLHostVerifyPrefix             = @"verify";
             DDLogWarn(@"Application opened with an unknown URL action: %@", url.host);
         }
     } else if ([url.scheme.lowercaseString isEqualToString:@"file"]) {
+
+        if ([Environment getCurrent].callService.call != nil) {
+            DDLogWarn(@"%@ ignoring 'open with Signal' due to ongoing WebRTC call.", self.tag);
+            return NO;
+        }
+
         NSString *filename = url.lastPathComponent;
         if ([filename stringByDeletingPathExtension].length < 1) {
             DDLogError(@"Application opened with URL invalid filename: %@", url);