British Prime Minister Gordon Brown on Wednesday plunged into crisis his campaign to win the general election on May 6, with an unguarded comment branding a 65-year-old woman who he had just talked with as "a bigot."

Brown, whose Labor party is trailing third in many polls, met the pensioner Gillian Duffy as he campaigned in a northern town. With a pack of journalists around them, Duffy questioned Brown about his policies and issues she felt strongly about.

After identifying herself as a Labor supporter who was ashamed of the party, she tackled Brown on one of the most popular issues in the election campaign, immigration.

"You can't say anything about the immigrants ... but there's all these Eastern Europeans coming in, where are they flocking from?" she asked.

Brown replied calmly, "A million people have come from Europe, but a million British people have gone into Europe."

He handled the other questions well, and seemed pleased with the encounter, and even put his arm around Duffy.

However, once Brown had returned to the safety of his car, he turned to aides and said, "That was a disaster. You should never have put me with that woman," forgetting he was wearing a microphone for TV.

"She's just a sort of bigoted woman," he added.

Brown's comments were still being broadcast live on TV channels by the microphone.

Labor officials tried to swiftly limit the damage. Lord Peter Mandelson, seen as one of the architects behind the electoral success of former Prime Minister Tony Blair in three successive elections, said he had spoken to Brown after the incident.

"There's no justification for it. Politicians are human. Sometimes you say things you simply do not mean. The moment you say it, you regret it, that's what all of us do. He doesn't believe this of Mrs Duffy, he doesn't believe this either in public or in private," Mandelson said.

The recording of what he said was later played to Brown as he gave an interview to a BBC radio program. A photographer captured a weary and unhappy prime minister with his head in his hands as he listened to his words.

He immediately apologized, "I apologize if I said anything like that. I blame myself for what is done. This was me being helpful to the broadcasters with my microphone on."

"I apologize profusely to the lady concerned," he said.

In a bid to further limit damage, Brown abandoned his plans for the afternoon's campaigning and traveled immediately to Duffy's home, where he spent over half an hour making a private apology to her, as the media waited outside.

When he emerged he claimed she had accepted his apology and that he was "a penitent sinner."

There have been similar gaffes in British politics before. The last Conservative Prime Minister John Major once confided with a TV interviewer while they were waiting for interview to start that he thought three members of his cabinet were "complete bastards" because they failed to back his policy on Europe. The indiscretion was caught on sound and became headline news.

Former Labor Deputy Prime Minister John Prescott once punched a protester who threw an egg at him, and his uppercut was caught by TV cameras and photographers. But the incident only served to make Prescott more popular. Brown may not be so lucky.

With only a week to go to the election, many opinion polls put Brown's governing Labor in third place, behind the Liberal Democrats, the third and largely ignored party in British politics for the past 90 years.

The Conservative party are out in front, with several polls showing their strength increasing, but not to the extent that they are due to win an outright majority in the election next week.