Media playback is unsupported on your device Media caption Nigel Farage says portraying his party as harbouring candidates with extreme views is "completely wrong".

Nigel Farage has defended his "difficult" decision not to contest Tory-held seats, insisting he was putting "country before party".

The Brexit Party leader told the BBC's Andrew Neil that his party had stopped the "Lib Dem surge" and were "tearing chunks out of the Labour vote".

He said his party was the challenger in Labour-Leave areas in next week's poll.

It comes as three Brexit Party MEPs quit to support the Tories, saying the party will split the pro-Brexit vote.

Annunziata Rees-Mogg, Lance Forman and Lucy Harris resigned the whip on Thursday, with Ms Rees-Mogg - Tory minister Jacob Rees-Mogg's sister - saying it was "tragic" that the Brexit Party "are now the very party risking Brexit".

Mr Farage announced in November that his party would not contest the 317 Westminster seats the Conservatives won in 2017, in order to help Leave-supporting candidates win.

Some have been critical of this decision, including MEP John Longworth, who lost the Brexit Party whip in the European Parliament on Wednesday for not support his leader's strategy. He is now backing the Conservatives.

Andy Wigmore, from the Leave.EU group Mr Farage fronted at the 2016 referendum, said the former Brexit Party MEPs had made the "right decision at the right time" to back the Conservatives.

"It's time for Nigel to join them," he added in a tweet.

During the 30-minute interview with Andrew Neil, Mr Farage was asked about his election strategy, Islamophobic remarks made by two of his candidates and whether the NHS should be "on the table" in any post-Brexit trade talks with the US.

The Brexit Party leader denied being marginalised at the general election.

Mr Farage said: "I don't think if you came with me and visited some of the Labour heartlands in the north you would think that and I also think that what we've done is have a very dramatic effect on this election.

"I think, number one, the decision, difficult decision, I took in 317 seats to stand down.

"What that's done is that's poleaxed the Liberal Democrats. They were going to win in south London down through Surrey, right out to the west of England they were going to win a lot of seats if we'd stood. And I knew that wasn't the right thing to do."

Image copyright PA Media Image caption The four former Brexit Party MEPs are urging voters to support the Conservative Party

Mr Farage claimed the Brexit Party had prevented a "surge" from the pro-EU Lib Dems and had, therefore, blocked a second EU referendum.

"What we are actually doing now is tearing chunks out of the Labour vote," he said.

He blamed his failure to form a so-called "Leave alliance" between his party and the Conservative Party for the election on the Tories.

"The Conservative Party didn't want to do it," he said.

Media playback is unsupported on your device Media caption Nigel Farage says three of the MEPs who have left his Brexit Party have links to the Conservative government

On his call for political reform, including scrapping the House of Lords and changing the voting system, he said: "At this stage we don't look like fundamentally reforming British politics, but do I think there is an appetite for it? Absolutely."

Mr Farage said he believed Boris Johnson would win the election and that was his preference in a choice with Labour leader Jeremy Corbyn.

But he said he was undecided who to vote for in the Conservative-held constituency where he lives.

'Ludicrous' NHS claims

Andrew Neil also challenged Mr Farage on Islamophobic comments made by two of his candidates in in Edinburgh South West and Birmingham Ladywood.

"Any attempt that gets made to try and paint the Brexit Party into being a right-wing political party that would harbour anybody with extreme views is completely and utterly wrong," he said.

"We are, in terms of the mix of our candidates, if I look at what we put forward for the European elections, we had more diversity of background, of class, of race, than any other party."

On Brexit, Mr Farage said he wanted to see "some amendments" to Mr Johnson's Brexit deal, saying: "If we don't we are not going to get a clean break from the EU."

And on whether he thinks NHS drug prices would be "on the table" in post-Brexit trade deal talks with the US, Mr Farage said the suggestion was "ludicrous because no British government will sign up to more expensive drugs".

He said he believed that "wealthier people should be encouraged to take out private insurance to lift the burden off a system that is struggling to cope".

"When it comes to opening up the NHS for privatisation, do you want the truth? It's already happened."

In a special series of election interviews, Andrew Neil has already questioned Labour leader Jeremy Corbyn, the SNP's Nicola Sturgeon and Liberal Democrat leader Jo Swinson.

Prime Minister Boris Johnson has yet to agree a date to taking part, which has prompted a political row and accusations from Labour that he is "running scared".