Tory former de-facto deputy prime minister Sir David Lidington has announced he will not stand in the forthcoming general election.
The Aylesbury MP’s decision comes after his former Cabinet colleague Amber Rudd said she too would stand down as an MP ahead of the poll in December.
Sir David cited the “heavy cost” of politics on family life in a letter to The Bucks Herald newspaper.
He said: “After a great deal of thought I have decided not to seek re-election at the forthcoming general election.
“Politics imposes a heavy cost on family and private life. That is not a complaint: people who seek elected office do so voluntarily.
“But I have come to the conclusion that now is the right time for me to give a higher priority in terms of my time and energy, to Helen and my family who have given unstinting support to me during more than a quarter of a century in the House of Commons.”
Former Tory home secretary Amber Rudd, who had a majority of just 346 at the last election in her Hastings and Rye constituency, said she was not “finished with politics” but was “just not standing at this election”.
She resigned from the Cabinet and surrendered the Tory whip over Brexit in September, but told the Evening Standard she would be leaving the Commons on “perfectly good terms” with Boris Johnson.
Her decision last month to quit the parliamentary party came after 21 of her colleagues lost the Tory whip when they backed a plan to take control of the Commons timetable to pass legislation to block a no-deal Brexit.
Ten of the MPs had the whip restored on Tuesday evening.
Asked if she had any regrets, Ms Rudd said: “I felt I made the right steps at those critical points and I am pleased that the Prime Minister has now restored the whip to some of those colleagues.”
She did not rule out a return to Westminster in the future, but said there were “many other things I want to do”.
Ms Rudd claimed on Twitter that she last week declined an invitation from Mr Johnson to stand in the general election for the Conservatives.
Responding after the publication of a letter from chief whip Mark Spencer telling her he was “not in a position to return the Conservative Whip” to her, she tweeted: “Funny thing really, as just last week the PM asked me to stand in the General Election.
“Afraid the Chief Whip has been briefed by the wrong ‘No 10 Sources’ this morning but nonetheless I respect the decision he had been asked to make.”
However a Number 10 source suggested that a meeting between Ms Rudd and Mr Johnson had not taken place.
Several other senior parliamentarians have also announced that they will not stand at the forthcoming election in December.
Conservative grandee Sir Patrick McLoughlin, who has served as Chancellor of the Duchy of Lancaster, Transport Secretary and Conservative Party chairman, said he would not seek reelection in his Derbyshire Dales constituency.
Sir Patrick said he felt it was “now time for me to move on” after 33 years in Parliament.