Federal prosecutors, meanwhile, claim that a 'substantial' prison term is warranted for Michael Cohen
Donald Trump's former personal lawyer Michael Cohen has offered significant assistance in the ongoing Russia probe, the US special counsel has said.
Robert Mueller - who is investigating alleged Russian interference in the 2016 US election - overnight released a sentencing memo concerning Mr Cohen.
It says that the lawyer committed a 'serious crime' by withholding information and lying to Congress - including about a proposed Trump-branded hotel project in Moscow.
However, it adds that Cohen has taken 'significant steps to mitigate his criminal conduct'.
According to Mueller's document, the lawyer has provided information about his own contacts with Russian interests, as well as "information about attempts by other Russian nationals to reach the campaign".
He's also said to have provided "relevant and useful" information about his contacts with people connected to the Trump White House in 2017 and 2018.
Meanwhile, federal prosecutors submitted a separate memo ahead of Mr Cohen's planned sentencing next week over four crimes - including tax evasion and making false statements to Congress.
The document highlights that Mr Cohen paid two women 'hush money' to remain quiet about alleged affairs with Donald Trump - claiming that the lawyer acted "in coordination with and at the direction" of Trump himself.
The prosecutors claim that a 'substantial' prison term is warranted, and that the lawyer's calls for no prison time other than 'time served' are 'meritless'.
Meanwhile, another memo from the special counsel claims that Trump's former campaign chair Paul Manafort told "multiple discernible lies" in interviews with both Mueller's office and the FBI.
The special counsel last month accused Mr Manafort of breaching a plea agreement.
In the new memo, it's claimed the veteran lobbyist lied over at least five subjects - including about interactions with a man with suspected links to Russia's intelligence services.
It further alleges that Mr Manafort also lied about his contact with Trump officials, saying he had 'authorised a person to speak with an administration official on Manafort's behalf' as recently as May 2018.
The memo concludes: "In his interviews with the Special Counsel's Office and the FBI, Manafort told multiple discernible lies - these were not instances of mere memory lapses".
The memos mark the latest developments in the ongoing investigations into both the ongoing Russia probe and the investigations into both Manafort and Cohen.
In the wake of the publication of the memos, President Trump took to Twitter - appearing to suggest they 'totally clear' him, although it was unclear what exactly he was referring to.
Totally clears the President. Thank you!— Donald J. Trump (@realDonaldTrump) December 7, 2018