Boris Johnson is preparing to effectively dare rebels to vote down his entire package of Covid-19 measures this week if the Commons Speaker blocks a vote designed to give MPs a say on new restrictions.
A growing number of MPs are rallying around an amendment tabled by Sir Graham Brady, the chairman of the 1922 committee of Tory backbenchers, which would force a vote on future social restrictions before they are imposed.
With some 60 Conservatives preparing to back the move, Mr Johnson would face his first parliamentary defeat since his landslide election win if opposition parties also vote against the Government en masse.
But ministers believe Sir Lindsay Hoyle, the Commons Speaker, will rule the amendment "out of scope" of Wednesday's motion on the first six-month renewal of the Coronavirus Act - despite allies of Sir Graham having received advice to the contrary.
If the amendment cannot be debated, Downing Street is understood to be preparing to rebuff calls to put forward its own mechanism to allow votes in advance of each future measure like the requirements to wear face masks and avoid gatherings of more than six people.
The move would leave Conservative MPs faced with the "nuclear" option of voting against the renewal of the entire Act, which the vast majority of the group of up to 60 rebels would avoid doing.
The legislation contains powers ranging from the emergency registration of nurses and other healthcare workers to measures to ensure that court proceedings continue to take place during the pandemic.
Careless to ignore rebellion
On Saturday night, Andrew Mitchell, the former Chief Whip, who is preparing to support the amendment, said: "When the chairman of the 1922 committee leads a rebellion like this it would be an exceedingly careless Prime Minister that chose to ignore it."
Writing in The Telegraph, Steve Baker, another former minister who has repeatedly raised concerns about curbs to freedoms as a result of the Government's measures to tackle Covid-19, states: "The consequences of taking away liberty to protect public health have been devastating to our society and economy by any standard.
"We must not now make a bad situation worse as we look to our future: we cannot spend our way out of this contraction, deficit or debt."
Mr Baker adds: "Please Boris, reach a deal with Sir Graham Brady to put Parliament where it belongs: right with you."
Downing Street has said it wants to "work closely" with MPs, with plans to offer more parliamentary debates and "symbolic" votes.
It has brought forward a retrospective vote on the “rule of six” to October 6. This weekend a No 10 spokesman said: “We have been clear that it is vital that we can take action to stop the transmission of the virus and protect the NHS."