A new round of trade negotiations between the United States and China has started in London, with both sides trying to preserve a fragile truce brokered last month.

Wall Street's main indexes were mixed on Monday as investors watched a fresh round of U.S.-China negotiations aimed at mending a trade rift that has rattled financial markets for much of the year. Top officials from both countries have kicked off discussions at London's Lancaster House,

US stocks flipped between small gains and losses early on Monday as investors awaited the outcome of crucial trade talks between Washington and Beijing in London.