diff --git a/tools/gpg-wks-client.c b/tools/gpg-wks-client.c
index c8ff16651..78e4fe420 100644
--- a/tools/gpg-wks-client.c
+++ b/tools/gpg-wks-client.c
@@ -1151,6 +1151,7 @@ encrypt_response (estream_t *r_output, estream_t input, const char *addrspec,
   ccparray_put (&ccp, "--status-fd=2");
   ccparray_put (&ccp, "--always-trust");
   ccparray_put (&ccp, "--armor");
+  ccparray_put (&ccp, "-z0");  /* No compression for improved robustness.  */
   if (fake_submission_addr)
     ccparray_put (&ccp, "--auto-key-locate=clear,local");
   else
diff --git a/tools/gpg-wks-server.c b/tools/gpg-wks-server.c
index 1a0ba8f4f..f83ef6528 100644
--- a/tools/gpg-wks-server.c
+++ b/tools/gpg-wks-server.c
@@ -586,6 +586,7 @@ encrypt_stream (estream_t *r_output, estream_t input, const char *keyfile)
   ccparray_put (&ccp, "--always-trust");
   ccparray_put (&ccp, "--no-keyring");
   ccparray_put (&ccp, "--armor");
+  ccparray_put (&ccp, "-z0");  /* No compression for improved robustness.  */
   ccparray_put (&ccp, "--recipient-file");
   ccparray_put (&ccp, keyfile);
   ccparray_put (&ccp, "--encrypt");