Tory MP Nick Boles, who quit his local party on Saturday over his stance on Brexit, says his priority lies with his constituents and he will not be “bossed around by a small number of people”.
He told the Andrew Marr Show he thought about standing as an independent MP.
But he said he had decided to remain as he was not “ready to give up on the Conservative Party yet”.
Mr Boles, MP for Grantham and Stamford, has been an outspoken critic of leaving the EU with no deal.
The MP – who is in favour of a closer Norway-style relationship with Europe – said he was “proud” of his role in the cross-party campaign to force the prime minister to request an extension to Article 50 beyond 29 March, and to block a no-deal Brexit.
But Councillor Martin Hill, vice president of the Grantham and Stamford Conservative Association, told members they had been “betrayed by their parliamentary representative”, calling on him to take the “honourable course” and quit as an MP.
‘In the best interest’
Mr Boles said a “certain amount of pressure was applied” by the local party after he was asked to tell them if he intended to stand as their representative at the next general election.
But he told the BBC’s Andrew Marr: “I represent 100,000 people in Parliament. I have roughly 500 members in my local association and roughly 60 people on my executive.
“I’m afraid I’m going to claim the right to interpret what is in the best interest of the 100,000 people I represent and I’m not going to be bossed around by a very small number of people with very ideological views.”
Despite leaving the local association, whose members he wrote to this weekend, Mr Boles said he remains loyal to the party.
He said: “I have voted for Theresa May’s deal every time it has been offered and I will vote for it again on Tuesday.
“The only thing and, in truth , the real area where I fell out with some members of my association, was in my efforts to stop a no-deal Brexit – and obviously I was very much involved in this plan that reached its fruition last week to stop a no-deal Brexit.”
He said he had been told he could continue as a Conservative MP, with his membership being transferred from his local party to the national party. He is to meet the chief whip on Monday.
The third “meaningful vote” on Prime Minister Theresa May’s deal is expected to take place next week. If it is agreed, she has promised to seek a short extension to the departure date.
But if it does not gain support, she has warned a longer extension may be needed – and the UK might have to take part in European elections.