Will Donald Trump be arrested on Tuesday?

Donald Trump claims he will be arrested on Tuesday on charges stemming from an investigation into a $130,000 payment to porn star Stormy Daniels in 2016.

In 2016, adult film star Stormy Daniels contacted media outlets offering to sell her account of what she said was an adulterous affair she had with Donald Trump in 2006.

Mr Trump's team got wind of this, and his lawyer Michael Cohen paid $130,000 to Ms Daniels to keep quiet.

This is not illegal. However, when Mr Trump reimbursed Mr Cohen, the record for the payment says it was for legal fees. Prosecutors say this amounts to Mr Trump falsifying business records, which is a misdemeanour - a criminal offence - in New York.

Prosecutors could also potentially allege that this breaks election law, because his attempt to hide his payments to Ms Daniels were motivated by not wanting voters to know he had an affair with her. Covering up a crime by falsifying records would be a felony, which is a more serious charge.

Even advocates for prosecution acknowledge that either way, this is by no means a clear-cut case. There is little precedent for such a prosecution, and past attempts to charge politicians with crossing the line between campaign finance and personal spending have ended in failure.

"It's going to be tough," says Catherine Christian, a former financial prosecutor for the New York City district attorney.

The decision on whether to file charges rests with New York City District Attorney Alvin Bragg. He set up the grand jury to investigate whether there was enough evidence to pursue a prosecution, and he is the only one who knows if - or when - an indictment will be announced.

Last week, Mr Trump lawyers said that the former president was offered a chance to appear before the grand jury, which is considered a sign that the investigation is close to finishing.

The former president's lawyers have downplayed suggestions that they or Mr Trump have any advance notice of an impending indictment, saying Mr Trump's comment about it being Tuesday were based on media reports.

However there are other signs that the grand jury is wrapping up. Both Michael Cohen and his former legal adviser Robert Costello - now a sharp critic - are expected to give testimony on Monday.

Mr Costello would be presented by Mr Trump's defence team in an attempt to discredit Mr Cohen's testimony.