Rebel Tory MPs opposed to England's national lockdown have formed a powerful new campaign group to turn up the heat on Boris Johnson and his stance on COVID-19.
Ominously for the prime minister, they are led by a former chief whip Mark Harper, and Brexiteer Steve Baker, mastermind of parliamentary guerrilla campaigns.
And in a move that will ring alarm bells in Downing Street, the group also includes Sir Graham Brady, chairman of the 1922 Committee of backbench Conservative MPs.
The new group, mostly made up of Tory MPs who rebelled in the Commons vote last week to approve the current lockdown, is calling itself the COVID Recovery Group.
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Mr Harper, who chairs the new group, said: "Last week I voted against a Conservative government for only the second time in my fifteen years in Parliament, which was not easy for a former chief whip.
"Lockdowns cost lives, whether in undiagnosed cancer treatments, deteriorating mental health, and missed A&E appointments - not to mention the impact it has on young people's education, job prospects and our soaring debts.
"The cure we're prescribing runs the risk of being worse than the disease.
"The COVID Recovery Group will play its part in helping the government to deliver an enduring strategy for living with the virus, so that we break the transmission of the disease, command public support, end this devastating cycle of repeated restrictions and start living in a sustainable way until an effective and safe vaccine is successfully rolled out across the population."
Mr Baker, MP and deputy chairman of the group, added: "This is about ensuring that our response to COVID is rational and balanced, taking account of the non-COVID health and economic consequences of restrictions and not being driven by panic.
"We must find a more sustainable way of leading our lives until a vaccine is rolled out, rather than throwing our prosperity away by shutting down and destroying our economy, and overlooking the untold health consequences caused by lockdowns and restrictions.
"The country is crying out for a radically different and enduring strategy for living with the virus and the COVID Recovery Group will assist the government in leading the UK out of the coronavirus crisis and into a positive future."
Other rebels on the new campaign's steering group include Adam Afriyie, Chris Green, who quit as a junior ministerial aide over lockdown measures, Philip Hollobone, Sir Robert Syms and William Wragg.
As well as rebels, the steering group also includes Dr Ben Spencer, a psychiatrist who is MP for former Chancellor Philip Hammond's Surrey stockbroker belt seat of Runnymede and Weybridge, and ex-ministers Harriett Baldwin and Nus Ghani.
Launching the group, the MPs have published what they call Three Guiding Principles, in which they are calling on the government to:
Undertake and publish full cost-benefit analysis of restrictions on a regional basis
End the monopoly on advice of government scientists
Improve the measures we already have to tackle the virus, including significantly boosting the performance of NHS Test and Trace by shifting resources to local public health teams to lead contact tracing and break the chain of transmission, and expanding the NHS' surge capacity.
The MPs claim: "Lockdowns and restrictions cost lives, push death and suffering into the future and cause immense economic, social and non-COVID health damage.
"Even a Department of Health and Social Care report has shown that the first lockdown led to more cancer deaths, deteriorating mental health and many other social harms.
"As well as prioritising the treatment of patients for COVID-19, we must give equal regard to the most lethal killers we face today - cancer, dementia, heart disease, and, for under 40s, suicide, to people's mental health, and the health implications and consequent mortality of falling GDP.
"MPs must be in a position to assess the relative health implications on both sides of the argument of repeated restrictions with a view to removing them immediately if it cannot be proved that they are saving more lives than they cost."
On scientific advice, the MPs claim: "We must allow prevailing expert scientific opinion to be challenged by competitive, multi-disciplinary expert groups - with challenges from devil's advocate 'red teams' - and publish the models that inform policies so they can be reviewed by the public.
"We have recently seen the modelling for coronavirus fatalities challenged and dismantled due to their use of outdated data.
And on test and trace, the MPs complain: "The current test and trace system has been reaching only 48% of the contacts of those who have tested positive and improvement is needed.
"The Scientific Advisory Group for Emergencies says that for the system to be effective, it needs to reach 80%.
"During lockdown we must transform the effectiveness of NHS Test and Trace so that we have another tool to help prevent repeated cycles of damaging lockdowns and restrictions."
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