Steve Bannon, a close ally of former president Donald Trump, has asked the Supreme Court to delay his four-month prison sentence while he appeals against his conviction.

He was found guilty nearly two years ago on contempt of Congress charges, after he defied a subpoena from the congressional committee investigating the 6 January riot in Washington.

A judge ruled that Bannon must report to prison to serve his sentence by 1 July. His appeal against that decision was denied on Thursday by a federal appeals court, so the Supreme Court remains Bannon's last chance at delaying his prison term.

Peter Navarro, another Trump adviser, failed a similar bid to overturn his contempt of Congress sentence and is currently serving time in prison.

A court document filed on Friday notes that Bannon "is not likely to flee or pose a danger to the safety of any other person or the community" if his sentence is delayed while he appeals against his conviction.

As he works to delay his own prison sentence, Bannon has regularly alleged that he and Trump's perceived political opponents will be incarcerated if the former president is re-elected.

On a recent episode of his War Room podcast, Bannon said that Andrew McCabe, an ex-FBI deputy director, "should be worried" that another Trump administration would "come and get you".

He also said that federal agencies would be "purged" under Trump and that that Manhattan District Attorney Alvin Bragg, who led the effort to convict the former president for falsifying business records, would be "jailed".

Trump later shared an article about Bannon's comments to millions of his followers on social media. Both men have alleged that the White House has weaponised the justice department against them.

Mr McCabe, who was fired from the FBI for leaking to the press during the Trump administration, struck back at Bannon and the former president during an interview with CNN on Thursday.

He called Trump and Bannon "paranoid, old" men who are "obsessed with personal grievances and settling scores" against their perceived foes.

"Their entire way of thinking about leading and administrating this country is in the context of having been wronged and trying to endanger support among their supporters by throwing this kind of red meat out to people who respond to this sort of language," he said.

Trump, for his part, has repeatedly suggested that he may seek out revenge on his political opponents if he emerges victorious from the November US election.

Mr McCabe was responding to those insinuations in a previous interview, which sparked Bannon's attacks on his podcast.

The ex-law enforcement leader claimed that members of the US intel community were having "tortuous" conversation about whether they should consider leaving the US if Trump wins.

"Everything he says stands in direct contrast to the nation we think we are, the nation we have always been." Mr McCabe said.

Bannon said that the former FBI official would not escape prosecution under a future Trump administration.

"You should be very worried," he said on his podcast. "We have extradition treaties with virtually every country in the world...go ahead and run and run as far as you want. We're going to come and get you."