Boles said he could remain aligned with the Conservatives in parliament if it is offered "on acceptable terms." The former minister for skills said in a letter to his local party he was "not willing to do what would be necessary to restore a reasonable working relationship with a group of people whose values and views are so much at odds with my own."
"I regret that my relationship with you should end in this way. But a politician without principles is worthless." Britain’s 2016 EU referendum has split not only British towns and villages but also parliament, with both Conservative and Labour leaders struggling to keep their parties united.
Last month, eleven members of parliament from both main parties defected to form the Independent Group, in large part dismayed by the handling of Brexit. This week, lawmakers voted down Prime Minister Theresa May's divorce deal with the EU for a second time - by 391 to 242.
Boles backed May, but has urged the government to work with opposition parties on an alternative Brexit plan - which would likely lead to a closer relationship with the EU than many Conservatives are prepared to accept. May continues to fight to build support for her plan, which is expected to be put before lawmakers for a third time next week.
Julian Smith, the party's Chief Whip who is responsible for making sure lawmakers vote in support of the government, said Boles was a "valued member of the Conservative parliamentary party which I hope will continue to benefit from his ideas". Boles, who has represented his constituency since 2010, has been spearheading efforts to force the government to give greater parliamentary control over the Brexit process and has spoken in favour of a closer economic relationship with the EU.
Martin Hill, vice president of the Conservative association in Boles' constituency Grantham and Stamford, said Boles had been at odds with the local association for some time. "So this announcement does not come as a complete surprise, but the timing does leave at lot to be desired," he said.
Meanwhile, senior aides to the prime minister believe she will be forced to set out a timetable for her departure if she is to get her Brexit divorce deal passed, the Daily Telegraph reported. The aides believe she has lost the trust of eurosceptic lawmakers in her party and will have to make way for a new leader after the Conservative Party conference in October, the newspaper said.
(Reporting by Andrew MacAskill; Editing by Mark Potter and Clelia Oziel)