An aircraft supplier can have parts ready and a customer waiting yet be unable to ship while Washington holds up its licence. In Shanghai, Citi has

approval to establish a securities business after years of waiting.

Companies must invest, sign contracts and move production while the two governments negotiate. A board needs to know what can proceed now, what remains conditional and what could stop the business after the money has been spent.

Chinese President Xi Jinping and US President Donald Trump

met in Beijing and Washington this year. The summits of the Asia-Pacific Economic Cooperation (

Apec) forum in Shenzhen in November and of the Group of 20 (

G20) in Miami in December offer two further opportunities. Four meetings between the leaders of the world’s two largest economies create expectations. Work already begun gives those expectations substance.