Former Tory chancellor Philip Hammond has announced he is resigning as the MP for Runnymede and Weybridge after 22 years.
He claimed the prospect of running in the election presented him with the "acute dilemma" of running against the party he'd supported for all of his adult life.
"(If I did that) I would cease to be a member of the party," he said.
In a tweet he spoke of the "great sadness" that came with making the decision and in a letter to constituents said he was "aggrieved" to have had the whip removed.
Mr Hammond was one of 21 Tory MPs to have the the whip withdrawn in response to their support for the anti-no-deal-Brexit Benn Act
Several of the Tory rebels who had been sacked along with Mr Hammond had the whip restored, but the ex-chancellor, who was seen to be one of the group's ringleaders, did not.
Mr Hammond, who voted Remain in the EU referendum and supports close-ties with Europe post-Brexit, has become a divisive figure over his stance.
Brexit Party leader Nigel Farage described Mr Hammond as a "fraud" and said he would not be paying tribute to the long-standing MP.
Mr Farage claimed Mr Hammond's resignation showed that "as an independent, he wasn't even going to save his deposit and that's the truth of it".
Mr Hammond, who was upset to have not been invited back, told how "many parliamentary colleagues have defied the party whip on occasion without any action being taken against them".
He said he is "saddened" to find himself unable to stand as a Conservative after 45 years in the party but said he would not "embark upon a course of action" that could challenge at an election "the party I have supported all my adult life".
Mr Hammond said he will remain an "active party member" and will continue to make the case for doing whatever is necessary to deliver a trade and security partnership between the UK and the EU.
The 63-year-old thanked his constituents for allowing him 22 years of service.
"It has been a pleasure to serve you and I wish you all every good fortunes for the future. I shall miss you greatly," he said.
Meanwhile, Anne Milton, another one of the 21 Tory MPs who had the whip withdrawn, will stand as an independent in the General Election.
She posted on Twitter: "I wrote to the PM yesterday to tell him I felt unable to be a Conservative Candidate.
"I have considered very carefully what is best to do and will stand as an Independent Candidate at the next General Election."
Commenting on her decision, she said: "I want people in Guildford to have a choice at the General Election.
"I have a background outside politics, a wealth of experience and a strong track record of achievement."
She said she wants to represent her constituency without "being bound by party politics", adding: "People have become increasingly frustrated by political parties and their inability to work together for the common good and I believe Guildford needs a credible alternative."