WASHINGTON (REUTERS) - The publisher of the National Enquirer tabloid newspaper has struck a deal with US prosecutors to avoid charges over its role in paying hush money before the 2016 US presidential election to a former Playboy model who said she had an affair with President Donald Trump, prosecutors said on Wednesday (Dec 12).

As part of the deal, publisher American Media (AMI) admitted that it made the US$150,000 (S$200,000) payment to the woman, Karen McDougal, "in concert" with Trump's presidential campaign and agreed to cooperate with prosecutors.

The announcement by the prosecutors in New York marked another potentially worrisome legal development for Trump and came on the same day that his former personal lawyer, Michael Cohen, was sentenced to three years in prison in Manhattan in part for negotiating the payment to McDougal.

A spokesman for AMI declined to comment.

Lawyers for Trump could not immediately be reached for comment.

McDougal has said she had a months-long sexual affair with Trump years before he took office, and that she sold her story for US$150,000 to AMI but it was never published.

The incident involved a practice known as "catch and kill" to prevent a potentially damaging article from being published.

Under its non-prosecution agreement, AMI admitted that it bought the story to prevent McDougal from going public about the alleged affair before the election.

Cohen was sentenced for orchestrating hush payments to McDougal and another woman, adult-film star Stormy Daniels, in violation of campaign laws before the election, as well as other crimes.

AMI's chief executive officer David Pecker, a longtime friend of Trump and Cohen, had met with prosecutors to describe their hush-money deals with McDougal and Daniels ahead of the 2016 election won by Trump, the Wall Street Journal reported in August.

Pecker and another AMI executive were granted immunity as part of prosecutors' probe, Vanity Fair also reported over the summer.

A representative for Pecker could not be immediately reached for comment.

Federal law requires that the contribution of "anything of value" to a campaign must be disclosed, and an individual donation cannot exceed US$2,700. Trump on Tuesday denied the payments to McDougal and Daniels were campaign contributions.

"If it were, it's only civil, and even if it's only civil, there was no violation based on what we did," Trump said in an interview with Reuters.