Defence minister says party risks handing Labour leader keys to Downing Street if infighting is not brought under control

The defence secretary, Michael Fallon, has demanded military discipline from his cabinet colleagues after Conservative backbenchers said they would back the prime minister in sacking any disloyal ministers.

Echoing the prime minister’s tone as she issued a warning to the party on Tuesday, Fallon said the Tories risked handing the keys to Downing Street to the Labour leader, Jeremy Corbyn, if they did not bring infighting under control.

“In this summer of warm prosecco, I think we in the cabinet would also do well to reflect on those military virtues – loyalty, discipline, cohesion – that might better enable us first to concentrate our fire on a dangerous enemy in reach of Downing Street, somebody who would lower our defences, scrap our deterrent, weaken our response to terrorism,” he told a reception hosted by the Conservative-supporting Policy Exchange thinktank on Tuesday evening.

He also said the party needed to “better articulate again the moral case for lower taxation, for honest public financing, for wider opportunity, enterprise and ownership”, calling it the “Conservative case”.

Theresa May told to sack disloyal ministers by backbench MPs Read more

His intervention follows days of damaging conflict between cabinet colleagues, played out partly in public, as leaks from private meetings appeared in the press and ministers pointed the finger at each other.

Claims that the chancellor, Philip Hammond, had called public sector workers “overpaid” and made sexist comments appeared in newspapers last week and an anonymous cabinet colleague also accused him of trying to “frustrate Brexit” and viewing leave-supporting ministers as “pirates”.

The chancellor’s allies said the environment secretary, Michael Gove, was behind the leaks – a claim that was denied.

The international trade secretary, Liam Fox, told the BBC’s Sunday Politics: “I don’t know where the briefing is coming from, but I do know it’s got to stop. I think there’s too much self-indulgence, and I think people need to have less prosecco and have a longer summer holiday.”

Following reports that a letter of no confidence in the prime minister was circulating among some MPs, three senior members of the influential 1922 Committee, which represents rank-and-file Tory MPs, said they would support May in reestablishing discipline.

Graham Brady, its chair, told the Guardian the party was “clear that it is supporting Theresa May and there is no intention of holding a leadership election, which would be a huge distraction from the important job of government”. He added: “Colleagues on the backbenches are keen that the whole party should work together to serve the public interest.”

On Tuesday, Amber Rudd, the home secretary, told her cabinet colleagues to get on with their jobs and the prime minister was reported to have told a drinks reception for Tory MPs: “No backbiting, no carping”, saying their choice was “me or Jeremy Corbyn … and nobody wants that”.

The prime minister’s spokesman has also publicly acknowledged that she has been forced to order to ministers not to leak details of cabinet meetings, saying May would be “reminding them of their responsibilities”.