Any indictment and arrest of Donald Trump would be "politically motivated" and would "tell you everything you need to know about the radical left", says Mike Pence.
The former vice president hit out at reports Mr Trump will be arrested on Tuesday over hush money payments made to adult film stars Stormy Daniels and Karen McDougal.
"I'm taken aback at the idea of indicting a former President of the United States, at a time when there's a crime wave in New York City," Mr Pence told ABC News.
"The fact that the Manhattan DA [district attorney] thinks that indicting President Trump is his top priority, I think is just tells you everything you need to know about the radical left in this country.
Mr Pence, who served under Donald Trump in the White House from 2017 to 2021, added: "It just feels like a politically charged prosecution here."
Mr Trump, 76, was given a standing ovation as he arrived at a wrestling tournament in Oklahoma on Saturday evening, hours after he claimed he was set to be arrested on Tuesday.
The former president was cheered by the crowd and pumped his fist as he made his way to his seat, clad in his trademark blue suit and red tie and flanked by his security detail.
Earlier, he said "illegal leaks" from the Manhattan district attorney's office indicated he will be indicted.
Making the claim on his Truth Social platform, Mr Trump provided no evidence he had been directly informed of a pending arrest and did not say how he knew of such plans.
Law enforcement agencies are preparing for a possible indictment of Mr Trump as early as next week, NBC News reports.
Chris Sununu, the governor of New Hampshire, said the potential indictment was garnering sympathy for Mr Trump.
The moderate Republican, who is said to be considering running for the party's presidential nomination, told CNN he had spoken to a number of people who were not "big Trump supporters but they all said ... they felt he was being attacked".
The Manhattan district attorney's office declined to comment on Mr Trump's claim and a spokesman for the former president did not respond when contacted.
Manhattan District Attorney Alvin Bragg has apparently been investigating whether payments made to Stormy Daniels and Karen McDougal in 2016 broke state laws.
A grand jury in Manhattan has been hearing from witnesses, including former Trump lawyer Michael Cohen, who says he orchestrated payments to the women to silence them about sexual encounters they said they had with Mr Trump a decade earlier.
Mr Bragg's office is also said to be examining the way Mr Trump's company compensated Cohen for his work.
Cohen was jailed for three years in 2018 after admitting making the payments.
He also pleaded guilty to tax evasion and lying to Congress about the extent of negotiations between the Trump Organisation and a project to build a Trump Tower in Moscow.
Cohen claimed Mr Trump directed him to make the payments worth $280,000 (£230,000) to Stormy Daniels and Karen McDougal - something the former president denies.