WASHINGTON(REUTERS) - Adult film star Stormy Daniels, who once claimed she had an affair with US President Donald Trump more than a decade ago, is now free to tell her story, according to her manager.

Ms Daniels' manager Gina Rodriguez told Reuters that after a private lawyer for Mr Trump revealed that he had paid US$130,000 (S$170,800) of his own money to the porn star, there was in violation of a non-disclosure agreement with Ms Daniels about the matter. As a result, Ms Daniels believes she can now talk about it publicly.

"Yes, Stormy is going to talk," Ms Rodriguez said via direct message on Twitter. She did not immediately respond to a question about when and where Ms Daniels would be speaking publicly.

The payment to Ms Daniels, whose real name is Stephanie Clifford, was made during the 2016 presidential election campaign but the lawyer, Mr Michael Cohen, said he was working alone and that it was not a campaign expense.

"Neither the Trump Organisation nor the Trump campaign was a party to the transaction with Ms Clifford, and neither reimbursed me for the payment, either directly or indirectly," Mr Cohen said in a statement issued on Tuesday night.

Ms Daniels was quoted as saying in a 2011 interview with In Touch Weekly that she had an affair with Trump after they met at a Lake Tahoe golf tournament in 2006.

Mr Trump has denied having an affair with Ms Daniels.

The Wall Street Journal first reported in January that Trump lawyer Michael Cohen had paid US$130,000 to Ms Daniels in 2016, the year Mr Trump won the presidential election.

In his most detailed account yet of what happened, Mr Cohen said in his statement that the payment was a "private transaction". He did not explain why he made the payment or say whether Mr Trump was aware of it.

The White House referred questions about the payment to Mr Cohen.

Mr Cohen's statement was in response to a complaint filed at the Federal Election Commission by the Common Cause watchdog group.

Common Cause argued in its complaint that the payment amounts to a campaign contribution well in excess of the US$2,700 limit to the amount any individual can give, and it has asked the FEC to enforce campaign finance laws.

"The complaint alleges that I somehow violated campaign finance laws by facilitating an excess, in-kind contribution. The allegations in the complaint are factually unsupported and without legal merit, and my counsel has submitted a response to the FEC," Mr Cohen said.

"Just because something isn't true doesn't mean that it can't cause you harm or damage. I will always protect Mr Trump," Mr Cohen said, adding that he would not comment further.

Common Cause said on Wednesday that the timing and circumstances of the payment "make it appear that the hush money was paid to Ms Daniels in an effort to influence the election." It called on the FEC to conduct a full investigation.

The FEC confirmed it received Common Cause's complaint and declined to comment on the case.