Donald Trump’s ex-lawyer and fixer Michael Cohen is set to continue crucial testimony on Tuesday in the former US president’s New York hush-money trial, where Trump faces charges of allegedly falsifying records of payments to a porn actor to cover an affair.

Cohen’s testimony is seen as crucial to the prosecution’s arguments that the money paid to Stormy Daniels represented an election expense, because Trump and his campaign believed news of their sexual encounter would hurt his 2016 bid for the White House.

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In testimony on Monday, Cohen directly implicated Trump several times by telling the Manhattan courtroom that Trump had tasked him – on several occasions – to keep stories about sex out of the media’s glare as he ran for president.

“Stop this from getting out,” Cohen said Trump told him in reference to Daniels’s account of an alleged sexual encounter with Trump 10 years previously. Similar instructions were given when the Playboy model Karen McDougal was paid $150,000 in another hush-money arrangement.

“Make sure it doesn’t get released,” Cohen testified Trump told him.

Cohen said: “What I was doing was at the direction of and benefit of Mr Trump.” He later added: “Everything required Mr Trump’s sign-off.”

Cohen’s testimony is seen as crucial to the prosecution case as he had first-hand knowledge of Trump’s activities. However, Cohen is a controversial figure – he pleaded guilty to federal charges related to the payments – and reliance on his testimony is also a risk. He could be an unpopular witness with jurors.

The two men were once incredibly close, with Cohen famously once saying he would “take a bullet” for Trump.

The New York trial has kept Trump mostly away from the campaign trail as he seeks to return to the White House, except for weekend rallies. But it does not seem to have dampened his standing in the polls. In head-to-head matches with Joe Biden, Trump often narrowly leads the Democratic incumbent and Trump is performing especially well in the swing states that are crucial to November’s presidential election.

There are three other outstanding criminal cases involving Trump – one based on attempts to change the 2020 election result in Georgia, another on mishandling sensitive documents, and a third on Trump’s behavior during the January 6 attack on the Capitol.

All three of those have faced significant delays, and none seem likely to wrap up before the election.