Former US President Donald Trump, saying he will be arrested on Tuesday, has called on his supporters to protest.

Trump posted on his Truth Social account on Saturday that "illegal leaks" from the Manhattan District Attorney's Office "indicate" that the "far and away leading Republican candidate and former President of the United States of America will be arrested on Tuesday of next week."

He did not provide further details, but told supporters to protest and "take our nation back."

A spokesperson for the former president says there has been no notification of a pending arrest.

New York prosecutors have been investigating an alleged hush money payment made to a porn star, who claims she once had an affair with Trump.

US media are reporting that Trump could soon face the first criminal indictment against a former US president.