diff --git a/lib/cm-impl.h b/lib/cm-impl.h
index 1cb755e55b3d4efa0cee82e537b1d93198dc7e22..3d2cf2dbae41eb85f8b1d21f50a6342553515738 100644
--- a/lib/cm-impl.h
+++ b/lib/cm-impl.h
@@ -250,7 +250,7 @@ extern mpz_t* cm_ecpp_compute_cardinalities (int *no_card,
 extern void cm_ecpp_one_step2 (mpz_t *cert2, mpz_t *cert1, int i,
    const char* modpoldir,
    const char *tmpdir, bool verbose, bool debug, cm_stat_t stat);
-extern bool cm_pari_ecpp_check (mpz_t **cert, int depth);
+extern bool cm_pari_ecpp_check (mpz_t **cert, int depth, bool debug);
 
 
 /* internal functions related to timers and counters */
diff --git a/lib/ecpp.c b/lib/ecpp.c
index cf33041b9a4bc4a71ea777d6731a2162874da901..751cfbc2ae09275c2dae5ebd8b388e896a98b9c4 100644
--- a/lib/ecpp.c
+++ b/lib/ecpp.c
@@ -2,7 +2,7 @@
 
 ecpp.c - code for computing ECPP certificates
 
-Copyright (C) 2021, 2022, 2023 Andreas Enge
+Copyright (C) 2021, 2022, 2023, 2024 Andreas Enge
 
 This file is part of CM.
 
@@ -1860,7 +1860,7 @@ bool cm_ecpp (mpz_srcptr N, const char* modpoldir,
 
       if (check) {
          cm_timer_start (clock);
-         res = cm_pari_ecpp_check (cert2, depth);
+         res = cm_pari_ecpp_check (cert2, depth, debug);
          cm_timer_stop (clock);
          if (verbose)
             printf ("Time for ECPP check (%s): %.0f\n",
diff --git a/lib/pari.c b/lib/pari.c
index 4f104f696bafe3eb738aac4f96f0b86fb77651c2..f58571702baad9926f2bfaa3a9c59c2dd603d21e 100644
--- a/lib/pari.c
+++ b/lib/pari.c
@@ -1369,9 +1369,10 @@ static int primecertpartialisvalid (GEN c, bool type, bool verbose)
 
 /*****************************************************************************/
 
-bool cm_pari_ecpp_check (mpz_t **cert, int depth)
+bool cm_pari_ecpp_check (mpz_t **cert, int depth, bool debug)
    /* Given a complete ECPP certificate (after step 2) of length depth in
-      cert, use PARI to check it and return its validity. */
+      cert, use PARI to check it and return its validity.
+      If debug is true, some progress information is printed. */
 {
    pari_sp av;
    bool res;
@@ -1381,7 +1382,7 @@ bool cm_pari_ecpp_check (mpz_t **cert, int depth)
 
    c = cert_get_V (cert, depth);
 
-   res = (primecertpartialisvalid (c, true, false) == 1);
+   res = (primecertpartialisvalid (c, true, debug) == 1);
 
    avma = av;