Theresa May has been accused of silencing Eurosceptics while allowing her pro-European Business Secretary to resurrect "Project Fear" over plans for a post-Brexit customs partnership with the EU.

Greg Clark, the Business Secretary, suggested that 3,500 jobs at Toyota could be at risk if the Prime Minister bowed to pressure from other members of her Cabinet and dropped the plans.

Eurosceptic ministers thought they had "killed off" the plans after a meeting of the Brexit wars Cabinet last week amid concerns that it will lead to Britain staying in the Customs Union.

However, Mr Clark said it was still "on the table", adding that he feels "very strongly" and is "clear-eyed" about the need to protect jobs after Brexit.

He also suggested that a transition period on customs could be extended until 2024. Within minutes of his comments the CBI group of business leaders, which is campaigning for Britain to stay in the Customs Union, sent out supportive comments.

Amber Rudd, the former Home Secretary, and Justine Greening, the former Education Secretary - who are both pro-European - also offered Mr Clark their support for his comments.

His intervention prompted a furious backlash from Eurosceptics, who said that Mr Clark's intervention had been "licensed" by Downing Street.