High-level delegations from the United States and China are meeting in London to try and shore up a fragile truce in a trade dispute that has roiled the global economy.

By Kate Holton, Andrea Shalal and Alistair Smout LONDON (Reuters) -U.S.-China trade talks were set to extend to a second day in London as top economic officials from the world's two largest economies sought to defuse a bitter dispute that has widened from tariffs to restrictions over rare earths,