diff --git a/base/modules/psi_penv_mod.F90 b/base/modules/psi_penv_mod.F90
index d29ae90e..738fe22b 100644
--- a/base/modules/psi_penv_mod.F90
+++ b/base/modules/psi_penv_mod.F90
@@ -464,6 +464,7 @@ contains
 
   function psb_wtime()
     use psb_const_mod
+    use mpi_constants
 #ifdef MPI_MOD
     use mpi
 #endif