diff --git a/include/mbedtls/config_psa.h b/include/mbedtls/config_psa.h
index cb9c533813..d81c4db808 100644
--- a/include/mbedtls/config_psa.h
+++ b/include/mbedtls/config_psa.h
@@ -838,6 +838,7 @@ extern "C" {
 #define MBEDTLS_PSA_BUILTIN_KEY_TYPE_RSA_KEY_PAIR_IMPORT 1
 #define MBEDTLS_PSA_BUILTIN_KEY_TYPE_RSA_KEY_PAIR_EXPORT 1
 #define MBEDTLS_PSA_BUILTIN_KEY_TYPE_RSA_KEY_PAIR_GENERATE 1
+#define MBEDTLS_GENPRIME
 #define PSA_WANT_KEY_TYPE_RSA_KEY_PAIR_BASIC 1
 #define PSA_WANT_KEY_TYPE_RSA_KEY_PAIR_IMPORT 1
 #define PSA_WANT_KEY_TYPE_RSA_KEY_PAIR_EXPORT 1