US President Donald Trump was aware of efforts to keep a porn star and a Playboy centrefold silent in the days leading up to the 2016 election, newly released court records show.

However, federal prosecutors in New York have decided not to file any additional charges in their investigation of the illegal hush money payments made to silence both women, according to two people familiar with the matter, who wished to remain anonymous.

Court records released on Friday (AEST) offered new details about the role Mr Trump played in his campaign’s frenetic efforts effort to quash stories about his alleged affairs with porn star Stormy Daniels and Playboy model Karen McDougal.

The US Attorney’s Office in Manhattan declined to comment.

But prosecutors confirmed in a court filing made public on Thursday local time that they not only investigated Mr Trump’s then lawyer Michael Cohen but also whether other people may be criminally liable in the scandal, made false statements, gave false testimony or otherwise obstructed justice.

They did not reveal the other subjects of the investigation.

Mr Trump initially insisted he was unaware of the hush money payments that Cohen orchestrated to Ms Daniels and Ms McDougal, who claimed they had affairs with Mr Trump.

Mr Trump denies the allegations.

The search warrants revealed on Thursday cite phone records showing Mr Trump spoke on the phone with Mr Cohen at least five times between October 8 and October 28, as Mr Trump’s campaign sought to contain the impending stories.

On October 28, 2016, as Mr Cohen was finalising payments meant to secure Ms Daniels’ silence, the lawyer spoke by phone with Mr Trump for about five minutes, and later traded texts with Ms Daniels’ lawyer Keith Davidson.

According to the documents, Mr Cohen thanked Mr Davidson and said: “I hope we’re good”.

“I assure you. We are very good,” Mr Davidson replied.

Mr Cohen, who pleaded guilty last year to campaign finance violations, lying to Congress and financial crimes, remains the only person to be charged in the scheme to protect Mr Trump’s reputation during the 2016 presidential campaign.

But prosecutors previously implicated the president in court filings, saying he directed Mr Cohen to arrange the hush money payments.

Mr Cohen’s lawyer Lanny Davis has argued others in Mr Trump’s orbit should have been indicted, and that prosecutors owe the public an explanation for why they weren’t.

Mr Cohen, who is serving a three-year prison term, released a statement through Mr Davis on Thursday.

“The conclusion of the investigation exonerating The Trump Organisation’s role should be of great concern to the American people and investigated by Congress and The Department of Justice,” Mr Cohen’s statement said.

Thursday’s release of documents came after US District Judge William Pauley granted a request by several media organisations.

Judge Pauley referred to the contents of the warrant on Wednesday as “a matter of national importance”.

-AAP