A New York grand jury considering whether to approve charges against Donald Trump over a hush-money payment to a porn actress has delayed an expected hearing.

US media reported that the grand jury will not meet as planned on Wednesday, citing law enforcement sources.

A Manhattan prosecutor may charge Mr Trump over how he declared a payment to keep quiet about an alleged affair.

It would be the first criminal case brought against a former US president.

It is unclear why the grand jury - which is set up by a prosecutor to determine whether there is enough evidence to pursue a prosecution - was asked not to reconvene.

It is scheduled to meet again on Thursday, but law enforcement sources told US media it is unlikely there will be a vote on whether to indict Mr Trump by the end of the week.

The grand jury has recently heard from the president's former lawyer, Michael Cohen, as well as from Robert Costello, a legal ally of Mr Trump. Mr Costello told media earlier this week that he offered testimony refuting allegations that the former president directed the pay-off.

He said on Wednesday that he does not expect to be called again as a witness. It is not known if the grand jury will hear from any other witnesses in the case.

CBS, the BBC's US partner, reported on Tuesday that Mr Trump was huddling with advisers at his Florida Mar-a-Lago home preparing for different scenarios.

On Saturday, Mr Trump said that he expected he would be arrested this week. In a post on his Truth Social platform on Wednesday, however, he said he believes charges against him "can't be brought."

Police in major US cities are preparing for potential unrest in case he is arrested as part of the hush-money inquiry.

Barricades have been set up outside the Manhattan criminal court and district attorney's offices.

Mr Trump has vowed to continue his campaign to become the Republican nominee in the 2024 presidential election regardless of any possible indictment.

He is scheduled to appear at a rally in Waco, Texas on Saturday, in support of his presidential bid.(BBC)

•Barricades set up outside the courthousein Manhattan by policeahead of a possible indictment of Donald Trump