In terms of manifestos of the Tories and the BNP, you can hardly tell the difference

Edgar Griffin, Montgomery Conservative Association

His family links to the BNP are well established - as well as his son's role, his wife Jean stood for the party against Mr Duncan Smith in the last election.

He also faces claims that he manned the phones at BNP party headquarters - allegations he denies.

Mr Griffin said he may have answered a BNP membership phone line, installed at his home because his wife is a party official, and answered questions about BNP policy.

However, as the Tory leadership contender moved to distance himself from Edgar Griffin, he said that he would be prepared to resign if he had embarrassed Mr Duncan Smith.

Two phones

Mr Griffin, 79, said that he may have "quite inadvertently" picked up the BNP phone line while his wife was out of the house.

"The phone rang and I had no option other than to pick it up," he said.

Monmouth AM David Davies attacked the alleged link

Asked about BNP policies, Mr Griffin told the BBC: "The BNP isn't an extreme right party at all, they're right in the middle, they're very trade union orientated."

He added: "The Tory party as a whole is bitterly opposed to the Asylum seekers and so is the BNP I understand."

'Not tolerated'

Mr Duncan Smith said he "utterly abhors" BNP views and had "fought racism all his life".

The campaign team said it was unaware of the alleged connection and had contacted Welsh Conservative officials, urging swift action over the claims.

Mr Griffin's name is on letterheads used by the Tory leader hopeful.

Mr Duncan Smith said of the BNP: "I have fought them in my own constituency. I utterly abhor their views and what they stand for.

"I will not tolerate people who are infiltrating the Tory party."

Conservative vice-chairman Stephen Norris, who is backing Ken Clarke in the two-horse race to be leader, said the row showed that Mr Duncan Smith's campaign was attracting the wrong sort of people.

Mr Norris said Mr Duncan Smith had not done enough to distance himself from Edgar Griffin.

He said: "Iain's problem is that however nicely he says it, his message attracts precisely these sorts of people.

"That's why so many of us are so determined to stop the party drifting to the right.

Edgar Griffin's son Nick polled 6,500 votes in Oldham West

Edgar Griffin, a retired accountant, said he remained a committed Tory and was not a BNP supporter. But he likened the two parties' policies.

"They are a democratic party and, in that regard, obviously they have my sympathy," he said.

"The two parties are almost the same in terms of long-term plans. In terms of manifestos of the Tories and the BNP, you can hardly tell the difference."

'Greatly disturbed'

In a BBC Wales interview on Thursday he said he would be led by Mr Duncan Smith's wishes.

"If he wants me to resign I will do it immediately....rather than be a thorn in Iain Duncan Smith's side, if he was embarrassed by it, I said I would resign from his campaign team, much against my wishes..... I don't think I am an embarrassment".

But he also remained defiant, describing the row as little more than a "storm in a teacup".

Henry Lloyd Davies, chairman of the Conservative Party in Wales, told BBC Wales he has received a personal assurance from Mr Griffin that he has never worked in the BNP office and saw no reason to pursue the matter further.

Mr Griffin's wife, Jean, ran for the BNP against Mr Duncan Smith in the Chingford and Woodford Green constituency at the 2001 general election.

She came last with 2.9% of the vote while the Conservative member retained his seat with 48.2%.

Of his wife's political affiliations, Edgar Griffin said: "She's her own woman - if she's BNP that's up to her."