Donald Trump directed his personal lawyer to make illegal hush payments to two women ahead of the 2016 election, US prosecutors said on Friday.

In court filings that revealed details of how Michael Cohen has helped the Russia investigation, prosecutors also detailed a previously unknown attempt by a Russian to help the Trump campaign.

Prosecutors in New York asked a judge to sentence Cohen to a "substantial term of imprisonment" for paying an adult film star hush money on Mr Trump's behalf, and for evading taxes. Cohen pleaded guilty to the charges in August.

He has been cooperating with Mr Mueller's probe into possible collusion between Russia and Mr Trump's 2016 election campaign.

Cohen also pleaded guilty last week to a separate charge brought by Mr Mueller's office that he lied to Congress about discussions over the construction of a proposed Trump Organisation skyscraper in Moscow.