Eighty Conservative MPs will vote against the Chequers plan, according to the former Brexit minister Steve Baker.
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His European Research Group of Conservative MPs says it will set out some alternative plans for Brexit, although not a full manifesto that some had talked about.
There are also Tory MPs on the other side of the Brexit argument who are threatening to leave the party if Boris Johnson were ever to become leader.
With just 200 days to go until the UK exits the EU, the febrile atmosphere in and out of Westminster shows no sign of easing.