diff --git a/src/nix/sigs.cc b/src/nix/sigs.cc
index 45cd2e1a6..12d965ffb 100644
--- a/src/nix/sigs.cc
+++ b/src/nix/sigs.cc
@@ -2,6 +2,7 @@
 #include "shared.hh"
 #include "store-api.hh"
 #include "thread-pool.hh"
+#include "progress-bar.hh"
 
 #include <atomic>
 
@@ -173,6 +174,7 @@ struct CmdKeyGenerateSecret : Command
         if (!keyName)
             throw UsageError("required argument '--key-name' is missing");
 
+        stopProgressBar();
         writeFull(STDOUT_FILENO, SecretKey::generate(*keyName).to_string());
     }
 };
@@ -194,6 +196,7 @@ struct CmdKeyConvertSecretToPublic : Command
     void run() override
     {
         SecretKey secretKey(drainFD(STDIN_FILENO));
+        stopProgressBar();
         writeFull(STDOUT_FILENO, secretKey.toPublicKey().to_string());
     }
 };