diff --git a/tests/src/psa_crypto_helpers.c b/tests/src/psa_crypto_helpers.c
index 500451e..f2222cb 100644
--- a/tests/src/psa_crypto_helpers.c
+++ b/tests/src/psa_crypto_helpers.c
@@ -63,6 +63,14 @@
         psa_destroy_persistent_key( key_ids_used_in_test[i] );
     num_key_ids_used = 0;
 }
+
+void mbedtls_test_psa_purge_key_cache( void )
+{
+    size_t i;
+    for( i = 0; i < num_key_ids_used; i++ )
+        psa_purge_key( key_ids_used_in_test[i] );
+}
+
 #endif /* MBEDTLS_PSA_CRYPTO_STORAGE_C */
 
 const char *mbedtls_test_helper_is_psa_leaking( void )