Beijing on Thursday said it "firmly opposes" sweeping new US tariffs on its exports, vowing "countermeasures to safeguard its own rights and interests".

US tariffs "do not comply with international trade rules and seriously harm the legitimate rights and interests of the relevant parties", the Commerce Ministry said in a statement.

It called for Washington to "immediately cancel" sweeping new tariffs, warning they "endanger global economic development" and would hurt US interests and international supply chains.

"China urges the US to immediately cancel unilateral tariff measures and properly resolve differences with trade partners through equal dialogue," the ministry said, adding: "There is no winner in a trade war, and there is no way out for protectionism."

"Many trading partners have expressed strong dissatisfaction and clear opposition," the ministry added.

Trump on Thursday slapped a 34 percent tariff on goods from China. That's on top of the existing tax of 20 percent. (Agencies)