The chief executive of the American chip maker Nvidia visited Beijing on Thursday, days after the US issued fresh restrictions on sales of the only AI chip it was still allowed to sell to China. Jensen Huang’s surprise visit was on the invitation of a trade organisation, according to a social media account affiliated with state media. The official broadcaster China Central Television said Huang met Ren Hongbin, the head of the China Council for the Promotion of International Trade, where he said he hopes “to continue to cooperate with…