Former justice secretary David Gauke is to stand as an independent candidate in the general election.
Mr Gauke was among the MPs expelled from the Parliamentary Conservative Party by Boris Johnson after he voted against a no-deal Brexit.
It meant he could not stand as a Tory candidate in 12 December’s election.
He confirmed his decision to stand in South West Hertfordshire, where he has been the MP since 2005, at a political awards ceremony on Tuesday.
He told The Times: “I represent a form of liberal Conservatism, but the last few months have been increasingly uncomfortable…
“The principle issue of this general election is Brexit and I think that the Conservative Party has got it badly wrong.
“The easy thing to do would be to go quietly, but I feel that I have to make a stand and make the case that we are heading towards an outcome that we will deeply regret.”
Earlier, Gagan Mohindra was chosen as the Conservative candidate for the constituency.
Mr Mohindra is a member of Essex County Council and Epping Forest District Council.
Some parties are yet to choose their candidates for South West Hertfordshire, but Tom Pashby has been selected for the Green Party and Sally Symington will represent the Liberal Democrats.