diff --git a/ssh.h b/ssh.h
index da98b7c8..9aae2a5d 100644
--- a/ssh.h
+++ b/ssh.h
@@ -1086,6 +1086,7 @@ bool dh_is_gex(const struct ssh_kex *kex);
 struct dh_ctx;
 struct dh_ctx *dh_setup_group(const struct ssh_kex *kex);
 struct dh_ctx *dh_setup_gex(Bignum pval, Bignum gval);
+int dh_modulus_bit_size(const struct dh_ctx *ctx);
 void dh_cleanup(struct dh_ctx *);
 Bignum dh_create_e(struct dh_ctx *, int nbits);
 const char *dh_validate_f(struct dh_ctx *, Bignum f);
diff --git a/ssh2kex-client.c b/ssh2kex-client.c
index bff5b284..701d5fb7 100644
--- a/ssh2kex-client.c
+++ b/ssh2kex-client.c
@@ -87,17 +87,22 @@ void ssh2kex_coroutine(struct ssh2_transport_state *s)
             s->dh_ctx = dh_setup_gex(s->p, s->g);
             s->kex_init_value = SSH2_MSG_KEX_DH_GEX_INIT;
             s->kex_reply_value = SSH2_MSG_KEX_DH_GEX_REPLY;
+
+            ppl_logevent(("Doing Diffie-Hellman key exchange using %d bit modulus and hash %s with a server supplied group",
+                          dh_modulus_bit_size(s->dh_ctx),
+                          s->kex_alg->hash->text_name));
         } else {
             s->ppl.bpp->pls->kctx = SSH2_PKTCTX_DHGROUP;
             s->dh_ctx = dh_setup_group(s->kex_alg);
             s->kex_init_value = SSH2_MSG_KEXDH_INIT;
             s->kex_reply_value = SSH2_MSG_KEXDH_REPLY;
-            ppl_logevent(("Using Diffie-Hellman with standard group \"%s\"",
+
+            ppl_logevent(("Doing Diffie-Hellman key exchange using %d bit modulus and hash %s with standard group \"%s\"",
+                          dh_modulus_bit_size(s->dh_ctx),
+                          s->kex_alg->hash->text_name,
                           s->kex_alg->groupname));
         }
 
-        ppl_logevent(("Doing Diffie-Hellman key exchange with hash %s",
-                      s->kex_alg->hash->text_name));
         /*
          * Now generate and send e for Diffie-Hellman.
          */
diff --git a/sshdh.c b/sshdh.c
index 84173e80..1bd226a0 100644
--- a/sshdh.c
+++ b/sshdh.c
@@ -209,6 +209,14 @@ struct dh_ctx *dh_setup_gex(Bignum pval, Bignum gval)
     return ctx;
 }
 
+/*
+ * Return size of DH modulus p.
+ */
+int dh_modulus_bit_size(const struct dh_ctx *ctx)
+{
+    return bignum_bitcount(ctx->p);
+}
+
 /*
  * Clean up and free a context.
  */