diff --git a/src/libexpr/primops/fetchGit.cc b/src/libexpr/primops/fetchGit.cc
index 7aa98e0b..0c653995 100644
--- a/src/libexpr/primops/fetchGit.cc
+++ b/src/libexpr/primops/fetchGit.cc
@@ -219,8 +219,6 @@ static void prim_fetchGit(EvalState & state, const Pos & pos, Value * * args, Va
     } else
         url = state.coerceToString(pos, *args[0], context, false, false);
 
-    if (!isUri(url)) url = absPath(url);
-
     // FIXME: git externals probably can be used to bypass the URI
     // whitelist. Ah well.
     state.checkURI(url);
diff --git a/src/libexpr/primops/fetchMercurial.cc b/src/libexpr/primops/fetchMercurial.cc
index 9d35f6d0..97cda245 100644
--- a/src/libexpr/primops/fetchMercurial.cc
+++ b/src/libexpr/primops/fetchMercurial.cc
@@ -184,8 +184,6 @@ static void prim_fetchMercurial(EvalState & state, const Pos & pos, Value * * ar
     } else
         url = state.coerceToString(pos, *args[0], context, false, false);
 
-    if (!isUri(url)) url = absPath(url);
-
     // FIXME: git externals probably can be used to bypass the URI
     // whitelist. Ah well.
     state.checkURI(url);