Manufacturers are calling on Theresa May to revoke article 50 if she cannot strike a Brexit agreement this week, in the latest sign that the looming possibility of Britain leaving the EU without a deal is hammering confidence in the sector.

Make UK, the lobby group that represents 20,000 manufacturing firms, last night wrote to May and Labour leader Jeremy Corbyn saying it is “critical for the future of UK manufacturing businesses and their workforces that we bring the current uncertainty to an end”.

The letter from Make UK chief executive Stephen Phipson, seen by The Sunday Times, comes after two-thirds of the group’s members backed revocation of article 50 if May does not reach a deal by the April 12 deadline.

Phipson wrote: “The