The Prime Minister pressed on. The UK was facing some of the most difficult circumstances this country has faced for generations, he said, adding: “We are going to do the right thing by our people and our country tonight.”

He told the MPs: “I want our country to be as free as it possibly can be” by voting for the new Plan B restrictions.

There was an early win for the PM. Conservative MP Paul Bristow – who had been planning to rebel – left the meeting early and briefed journalists outside that he now would back the Government. “What is the alternative? Closing down nightclubs, closing down hospitality – that is the last thing we want to do,” he said.

A government minister left the meeting shouting at reporters that “the rebels are haemorrhaging”. Except they were not.

Within an hour, the scale of the rebellion was clear, with 100 Tory heading through the ‘no’ lobby on the issue of Covid certification in nightclubs and large venues, far more than the 60 MPs who had been expected.

On the plus side, not a single Parliamentary Private Secretary had resigned – even though whips said one had submitted his resignation letter only for the MP to withdraw it after receiving further reassurances from the PM himself.

‘Leadership challenge has got to be on the cards’

Worryingly for Mr Johnson, the rebels had come from across the party, from Covid sceptics like Steve Baker and Richard Drax to more moderate MPs like Stephen McPartland and Damian Green. Even the party’s newest MP, Louie French, elected just 10 days ago at the Old Bexley and Sidcup by-election, was in attendance.

There was no help for her successor from Theresa May, who herself was battered by Tory rebellions when she was PM, as she abstained. “It means everyone is f—– off,” one MP said.

Significantly, all six officers of the 1922 Committee – effectively its board – Sir Graham Brady (chairman), Sir Geoffrey Clifton-Brown (treasurer), Nusrat Ghani and William Wragg (vice-chairmen), Bob Blackman and Gary Sambrook (secretaries), had rebelled.

Then came the coup de theatre as Sir Geoffrey went on live television to say that a leadership challenge against Mr Johnson “has got to be on the cards”.

The veteran Tory said: “He has got to now be in some danger. He has got to realise that… If this goes on – we have had a very bad month in the last month – some members of the party will be thinking we have got to have a change.”