Cain's campaign manager says the Texas governor should apologise to Cain for providing information about the harassment allegations to the news media.
Perry's people deny any involvement in the story, and suggested the campaign of yet another candidate, Mitt Romney, might be a source.
Spokesman Ray Sullivan said the Perry campaign learned of the allegations when Politico first published the story late on Sunday evening.

Cain specifically blames a Perry consultant, Curt Anderson. He says he told Anderson about the s*xual harassment allegations when Anderson was working on Cain's 2004 Senate campaign.
Meanwhile, a third former employee considered filing a workplace complaint against Herman Cain over what she deemed aggressive and unwanted behaviour when she and Cain, now a Republican presidential candidate, worked together during the late 1990s, the woman told The Associated Press on Wednesday. She said the behaviour included a private invitation to his corporate apartment.

The woman said he made s*xually suggestive remarks or gestures about the same time that two co-workers had settled separate harassment complaints against Cain, who was then the head of the National Restaurant Association.
She did not file a formal complaint because she began having fewer interactions with Cain, she said. Afterward, she learned that a co-worker - one of the two women whose accusations have rocked Cain's campaign this week - had already done so. She said she would have had to file if they hadn't.

The woman spoke only on condition of anonymity, saying she feared losing her current job and the possibility of damage to her reputation. She was located and approached by the AP as part of its investigation into harassment complaints against Cain that were disclosed in recent days and have thrown his presidential campaign into turmoil. She said she was reluctant to describe the encounters she had with Cain when they worked together at the Washington-based restaurant trade group.
DOES HERMAN CAIN KNOW CHINA HAS NUCLEAR WEAPONS?
Away from the harassment allegations, he has had some foreign policy questions to answer.
Mr Cain appeared to bungle one of these when he suggested that China was trying to acquire nuclear weapons, which Beijing has in fact possessed since the 1960s.
'They've indicated that they're trying to acquire nuclear capability,' Mr Cain said in a PBS television interview on Tuesday. But on Wednesday he appeared to be trying to correct himself.
'I see China as a national security threat. They long for a military like ours,' he told technology executives in a Virginia suburb of Washington.
'They are testing in order to be able to improve their nuclear arsenal, so for us to think that if we just stay static - that they are going to stop trying to develop that military might - I think that is naive.'
He said his China strategy was for the U.S. to 'outgrow' the Far East country, gain economic leverage on issues like intellectual property and 'maintain our superiority'.
The employee described in conversations with the AP over several days situations in which she said Cain told her that he had confided to colleagues how attractive she was and invited her to his corporate apartment outside work.
His actions 'were inappropriate, and it made me feel uncomfortable,' she said.
Asked for comment about the accusations, including the most recent, Cain spokesman JD Gordon said: 'Mr Cain has said over the past two days at public events that we could see other baseless allegations made against him as this appalling smear campaign continues.' Mr Gordon added: 'He has never acted in the way alleged by inside-the-Beltway media, and his distinguished record over 40 years spent climbing the corporate ladder speaks for itself.'
The AP confirmed that the employee worked at the restaurant association with Cain during the period in question, that she has no party affiliation in her voter registration in the past decade and is not identified as a donor in federal campaigns or local political campaigns. Records show she was registered as a Democrat at one point previously.
Though trying to project an image of campaign business as usual, Cain appeared frazzled at times on Wednesday and couldn't escape the questions that have dogged him since a published report on Sunday night that at least two women had complained about his behaviour while at the restaurant association and had been given financial settlements. The controversy has arisen two months before the leadoff Iowa caucuses and as polls show Cain at the head of the GOP field alongside former Massachusetts Governor Mitt Romney.

In an interview with Forbes, Cain said he believes a consultant to Texas Governor Rick Perry, one of his GOP rivals, gave information about the allegations to Politico for the original report.
Perry's campaign denied it. 'No one at this campaign had anything to do with this story. We strongly reject the accusation, and learned of the allegations when we read Politico,' said spokesman Ray Sullivan.
'What are the facts? If you have a confidentiality agreement that keeps the public from finding out something that the public is interested in knowing the facts, you ought to go on and get the facts out. Herman Cain's interest is getting this behind him'
Mississippi Governor Haley Barbour
Cain said he outlined the allegations of a woman to the consultant, Curt Anderson, when Anderson was helping him on an earlier campaign.
Mr Anderson said in a statement to AP: 'I was one of several consultants on his Senate race in 2004 and was proud to help him. I never heard any of these allegations until I read about them in Politico, nor does anything I read in the press change my opinion that Herman is an upstanding man and a gentleman.'
Perry's campaign pointed to former Massachusetts Governor Romney's operation as a possible source of the Politico story. 'There are real ties between Romney campaign backers and Mr. Cain and the National Restaurant Association,' Mr Sullivan said.
As the day began, Cain said, 'There are factions that are trying to destroy me personally, as well as this campaign.' He didn't say to whom he was referring, but he said 'the voice of the people' is stronger.
Cain was supposed to take questions after a speech to health care professionals, but he ultimately refused and left the hotel through a back door.
'I'm here to visit with these doctors, and that's what I'm going to talk about, so don't even bother asking me all of these other questions that you all are curious about, OK? Don't even bother,' a testy Cain told a throng of reporters.

When pressed about the week's previous allegations, Cain raised his voice and said 'What did I say? Excuse me. Excuse me!' as hotel security led him through a hallway jammed with journalists in a Washington suburb. 'What part of "no" don't people understand?'
Meanwhile, another of Cain's accusers appeared increasingly reluctant to speak publicly, though her lawyer took the first steps for her to do so. Attorney Joel P Bennett contacted the association on Wednesday and asked it to release his client from the confidentiality arrangement she had agreed to so that she could talk openly about her allegations and respond to Cain's assertion that her complaints were 'totally baseless and totally false'.

Cain has declined to say whether he will ask his former employer to terminate confidentiality restrictions on the two women who accused him of sexual harassment in the 1990s while he was head of the trade group. Cain campaign manager Mark Block said the campaign would address that question 'when it's appropriate'.
Sue Hensley, a restaurant association spokesman, confirmed that Bennett contacted the trade group and was told to contact its outside counsel. Hensley said Bennett expected to meet with his client and make the request on Thursday.
Confidentiality agreements that commit both sides to silence are common in financial settlements of an employee's s*xual harassment claims, lawyers for management and employees said. Violating such an agreement can lead to a complaint in court and an order to pay damages, or at least the other side's attorney's fees, said Sarah Pierce Wimberly, a partner in the Atlanta office of the Ford and Harrison law firm.
But when the silence is broken, it's often hard to find the source of the leak, said Robert Kelner, a partner in the Covington and Burling firm's Washington office. He said, 'The truth is, when parties enter into these confidentiality agreements around a settlement, they usually understand that there is less than 100 per cent certainty that the information is truly going to remain confidential.'
It's not clear if Cain himself was part of the settlement or whether it just involved the association and the woman. But he almost certainly would be bound by it, as the association's former president.

Over the past two days, Cain has acknowledged he knew of one agreement between the restaurant association and a woman who accused him of s*xual harassment. He has said the woman initially asked for a large financial settlement but ultimately received 'two to three months' pay as part of a separation agreement. Cain also acknowledged remembering one of the woman's accusations against him, saying he stepped close to her to make a reference to her height and told her she was the same height as his wife.
'What did I say? Excuse me. Excuse me! What part of "no" don't people understand?'
Herman Cain
He has said he is not aware of agreements or settlements with any other women, though Politico - which first disclosed the allegations - reported that the trade group had given settlements to at least two female employees who accused him of inappropriate s*xual behaviour.
In media interviews since the story broke on Sunday, Cain has offered conflicting accounts of what happened during his tenure at the trade group in Washington. He later acknowledged knowing about one settlement but said he did not know how much was paid. The New York Times reported on Tuesday that one payout was $35,000, equivalent to one year's salary for one of the women.

The pressure on Cain only increased when a pillar of the GOP establishment suggested that the Georgia businessman should ask the association to waive the confidentiality agreements so that the woman can talk openly about her allegations.
'There are factions that are trying to destroy me personally, as well as this campaign'
Herman Cain
'What are the facts?' asked Mississippi Governor Haley Barbour on MSNBC. 'If you have a confidentiality agreement that keeps the public from finding out something that the public is interested in knowing the facts, you ought to go on and get the facts out.'
'Herman Cain's interest is getting this behind him,' added Mr Barbour, a former Republican National Committee chairman.
A former talk show host, Cain is a self-styled political outsider who has attracted tea party support and, up until now, has weathered a series of stumbles that have many GOP luminaries questioning his ability to run a viable campaign much less win the party's nomination. Conversely, Romney is running his second national campaign and has spent the past few weeks shoring up support among the GOP establishment for a nomination fight many Republican insiders think is his to lose.


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