BEIJING (AP) — China has threatened retaliation if President Donald Trump goes ahead with planned tariff hikes on Chinese goods. Trump stepped up a dispute over Beijing’s trade surplus and technology ambitions by announcing 10% tariffs effective Sept. 1 on $300 billion of Chinese imports. The Commerce Ministry said Beijing would be forced to take unspecified ‘necessary countermeasures.’ The ministry said Trump violated an agreement with President Xi Jinping in June to revive negotiations.