diff --git a/guix/packages.scm b/guix/packages.scm
index f373136d22..624d3d8c45 100644
--- a/guix/packages.scm
+++ b/guix/packages.scm
@@ -1320,7 +1320,16 @@ (define (package-direct-sources package)
                    ((_ (? origin? orig) _ ...)
                     orig)
                    (_ #f))
-                  (package-direct-inputs package))))
+                  (package-direct-inputs package))
+    (match (assoc #:phases (package-arguments package))
+      ((#:phases (? gexp? phases) . _)
+       (filter-map (lambda (input)
+                     (match (gexp-input-thing input)
+                       ((? origin? o) o)
+                       (_ #f)))
+                   (gexp-inputs phases)))
+      (_
+       '()))))
 
 (define (package-transitive-sources package)
   "Return PACKAGE's direct sources, and their direct sources, recursively."