WASHINGTON — US and Chinese officials are meeting in London today in a bid to preserve a fragile trade truce following renewed tariff clashes. Led by top US and Chinese economic officials, the talks follow a recent Trump-Xi phone call described as “very positive.” Despite a temporary tariff cut deal struck in Geneva last month, tensions remain high over issues like rare earth exports and compliance. China, meanwhile, is engaging with other partners, including the EU and Canada, to ease trade friction and counter US measures.