China's exports to the United States fell 35% in May from a year earlier, new customs data show, adding to pressure on the world's second largest economy as a new round of trade talks with Washington was due to start later Monday in London.

Chinese exports rose less than expected last month as the worst drop in shipments to the US in more than five years counteracted strong demand from other markets.

As was the case last month, the decline in exports to the U.S. was offset by a jump in outbound shipments to other regions of the world, including Southeast Asia and the European