Conservative peer Lord Heseltine has defended his decision to vote for the Lib Dems in the European elections, saying it is a “matter of conscience”.
The ex-deputy PM said he would not back the Tories in this week’s vote because of its pro-Brexit stance.
This has led to calls that he should be expelled from the party.
Conservative MP Andrew Bridgen said backing another party broke Tory rules while his colleague Conor Burns said “discipline needs to be enforced”.
The UK will take part in the elections for the European Parliament on 23 May after the government was unable to agree a Brexit deal.
Lord Heseltine’s revelation that he would be voting for the Liberal Democrats, disclosed in an article for the Sunday Times, has angered Tory Brexiteers.
Speaking to Emma Barnett on BBC Radio 5 live, Mr Bridgen said: “Lord Heseltine – in promoting voting for a non-Conservative candidate in an election where Conservative candidates are standing – is in breach of our party rules.”
“I find Lord Heseltine’s arrogance that he knows better than the majority of the electorate really quite breathtaking.
“There really is no place for someone with his views in the Conservative Party.”
But the 86 year-old, who served in the governments of Margaret Thatcher and John Major and was an adviser to David Cameron, said he would resist any attempts to force him out of the party.
He told 5 live: “I said quite clearly that I’m lending my support to the Liberal Democrat candidate.
“I’m not going to leave the Conservative Party and I’m not going to resign the Conservative whip – that’s where my natural home is.
“But I’m not prepared to indulge in this act of national sacrifice by voting for Brexit.”
He said he would be backing the candidate in his constituency that seemed the most likely to stop Brexit – which was a former Conservative MEP who was now standing for the Lib Dems.
It would be “a great sadness” for him if he was expelled from the party, he said, but he would continue to support Tory policies.
“People should vote for the national interest,” he added. “They should decide what they think is best for this country.
“This is not a matter of rules. It’s a matter of conscience.”
It is not the first time Lord Heseltine has been at odds with his party over Brexit.
In March 2017 he was sacked as a government adviser after rebelling in a Brexit vote in the House of Lords.
The UK is legally obliged to take part in this week’s European elections, which happens every five years in EU countries, after it failed to approve a withdrawal agreement by 22 May