diff --git a/src/expr.c b/src/expr.c
index 79782fa..db84d0b 100644
--- a/src/expr.c
+++ b/src/expr.c
@@ -29,8 +29,11 @@ struct nft_rule_expr *nft_rule_expr_alloc(const char *name)
 	struct expr_ops *ops;
 
 	ops = nft_expr_ops_lookup(name);
-	if (ops == NULL)
+	if (ops == NULL) {
+		fprintf(stderr, "libnftnl: Expression '%s' not supported\n",
+			name);
 		return NULL;
+	}
 
 	expr = calloc(1, sizeof(struct nft_rule_expr) + ops->alloc_len);
 	if (expr == NULL)