Boris Johnson compares his premiership to a Typhoon flight as he prepares to hand over the controls

Boris Johnson has compared his premiership to a Typhoon fighter jet flight as he prepares to hand over "the controls" to the next Conservative Party leader.

Last week, the prime minister was given a demonstration of the Typhoon fighter jet at RAF Coningsby in Lincolnshire - as the second round of voting in the ongoing Conservative leadership contest took place.

Downing Street has released footage of Mr Johnson at the controls of the fighter jet, and the PM is expected to compare the flight to his leadership of the Tory party later today.

"I hauled the joystick right the way back and we did a loop the loop," Mr Johnson is expected to say to business leaders at Farnborough air show.

'Stay at home' warning issued - UK heatwave latest updates

"After three happy years in the cockpit, performing some pretty difficult if not astonishing feats, I am about to hand the controls over seamlessly to someone else."

But Mr Johnson's visit to Farnborough comes at a time when he is facing criticism for not leading COBRA meetings being held in response to extreme temperatures.

Earlier today, Labour called on the PM to "turn up for work" after he missed two COBRA meetings on the heatwave and is set to be absent from a third briefing today.

Shadow communities secretary Lisa Nandy said the prime minister has "clearly clocked off" since announcing his resignation, adding: "And so have many of his ministers in his government."

The Labour minister said all members of the government should "turn up for work" when asked what more ministers could be doing to assist people as the country is set to record ferocious temperatures over the next 48 hours.

Her comments came after Mr Johnson missed the second COBRA meeting on the heatwave on Saturday, which was chaired by Chancellor of the Duchy of Lancaster Kit Malthouse.

A source told Sky News Mr Johnson was holding his farewell party at the prime minister's official country residence Chequers.

Formal invites went out earlier this week to the event being held in Buckinghamshire.

A Tory source told Sky News: "The invitation comes from Mr and Mrs Johnson.

"It is their farewell bash at Chequers this weekend. Partners and children are all invited."

Number 10 has confirmed the prime minister will also not be attending a COBRA meeting on the heatwave on Monday, which has been declared a national emergency.

A Number 10 source said Mr Johnson had been in contact with relevant ministers all weekend.

Probed on Mr Johnson's absence this morning, Mr Malthouse defended the PM and said he is "right across" the situation.

He said: "It's my job to chair COBRA meetings. I briefed him yesterday morning at about 8am personally."

On Mr Johnson's leaving do, a Number 10 spokesman said: "As this is not relevant to government business there is nothing to add."

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

Five Tory MPs are still in the race and they will be whittled down to two contestants by the end of this week.

The final two will then take part in hustings over the summer before Conservative Party members vote on who will replace Mr Johnson by 5 September.

The House of Commons' summer recess begins on Friday.