Boris Johnson has already “clocked off” from his job as Prime Minister, Labour claimed over his failure to lead Cobra meetings in response to the heatwave.

Cabinet Office minister Kit Malthouse, who has chaired the meetings, claimed it was unfair to criticise the Prime Minister and insisted Mr Johnson had been fully briefed on the situation.

The Prime Minister was at his country retreat Chequers over the weekend where he hosted a party for friends.

Shadow levelling up secretary Lisa Nandy said: “We think the Government ought to do a number of things: first is to turn up to work.”

She told Sky News the Prime Minister has “clearly clocked off”, adding: “And so have many of his ministers in his Government.”

Ms Nandy argued there should be a dedicated Cabinet Office minister to co-ordinate an emergency response and she urged Whitehall to work with local areas to ensure resilience plans are in place to end the current “patchwork” approach.

The Prime Minister is set to leave office in September following the election of a new Tory leader.

Allies said the gathering at Chequers was a “private informal event” and no taxpayers’ money was spent on it.

Chancellor of the Duchy of Lancaster Mr Malthouse said it was a “very unfair criticism” to attack Mr Johnson for not attending the Cobra meetings.

The Cabinet Office minister told LBC Radio: “It’s literally my job to chair Cobra. The Civil Contingencies Secretariat sits in my department.”

He said Mr Johnson “appoints secretaries of state to do this kind of work and that’s what I’ve been doing”.