Data presented by the Government's chief advisers to justify a second national lockdown in England has been "mathematically proven" to be incorrect, an Oxford University professor has said.
Carl Heneghan, director of the Centre for Evidence-Based Medicine at the University of Oxford, said a forecast suggesting 4,000 daily deaths next month was wrong.
The modelling, which was presented at a Downing Street press conference on Saturday is so outdated that it suggests daily deaths are now around 1,000 a day.
In fact, the daily average for the last week is 260, with a figure of 162 on Saturday.
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But the 4,000 figure was presented by scientists when Boris Johnson confirmed new nationwide restrictions would be imposed from Thursday for four weeks to prevent a "medical and moral disaster" for the NHS.
Prof Heneghan told the Today programme: "Mathematically it is now proven to be incorrect particularly the 4,000 estimate of deaths that would occur in December and why that is because it is already about four weeks out of date.
"And actually Cambridge who are doing it the MRC (Medical Research Council) unit have already provided updates to provide lower estimates and those estimates are much closer to the truth."
Prof Heneghan today urged Professor Chris Whitty and Sir Patrick Vallance to provide "really clear" information to MPs to explain why a second lockdown has been ordered when they appear in front of the Science and Technology Committee this afternoon.
He said the decision to impose new blanket restrictions must be made on "actual data" and not models that are "shown to be wrong", adding the Government's three-tier system was effective in bringing down coronavirus cases.
Speaking about Liverpool, where the strictest restrictions have been imposed, Prof Heneghan said cases had halved while hospital admissions had "stabilised".
"You've got ... these pockets around the country where trusts like Liverpool have got into trouble with over half the patients being Covid patients," he told the BBC.
"But let's look at the data, the data in Liverpool is showing cases have come down by about half, admissions have now stabilised, so, yes, there is a problem in Liverpool.
"But, actually, the tier restrictions... the people in Liverpool have dropped cases from about 490 a day down to 260 a day - a significant drop
"The R value is well below one in Liverpool at this moment in time."
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