China on Monday accused Washington of abusing tariffs and warned countries against striking a broader economic deal with the United States at its expense, ratcheting up its rhetoric in a spiralling trade war between the world's two biggest economies.Beijing will firmly oppose any party striking a deal at China's expense and "will take countermeasures in a resolute and reciprocal manner," its Commerce Ministry said. The ministry was responding to a Bloomberg report, citing sources familiar with the matter, that the Trump administration is preparing to pressure nations seeking tariff reductions or exemptions from the U.S. to curb trade with China, including imposing monetary sanctions.