Donald Trump may run for president again in 2024 if he loses this year's election, his former chief of staff has said.
Mick Mulvaney, US special envoy in Northern Ireland, said President Trump will not want to be remembered as a one-term leader.
He added that division in the United States was not caused by his presidency, rather the division was what led him to be elected.
It comes as Joe Biden has taken the lead in one of the key battleground states of the US election.
The former vice president is ahead in Georgia, which Donald Trump needs to have a path to victory.
The president has claimed the election is being stolen, without providing evidence, and has filed a number of lawsuits.
Mr Mulvaney told Newstalk Breakfast that if President Trump loses, he may return in four years to as a challenger for the White House again.
He said: "He's going to be younger in four years than Joe Biden is now.
"He killed me when I was chief of staff, I couldn't keep up with the guy and he's 25 years older than I am.
"Absolutely don't rule it out.
"Plus he's not going to want to go down in history as a one-term president.
"It's hard to make the case that you're a great president if you only won one term.
"He could erase a lot of blemishes on that record if he loses this year and runs again in 2024."
However, Mr Mulvaney said that Donald Trump will fight for the Presidency to the end.
He said: "Both of these men are heavily invested in this race.
"They have 65 to 70 million people behind them who are heavily invested in this race.
"These are the highest stakes probably in the whole world.
"They are going to fight to the bitter end, you're not going to see somebody throw up his hands halfway and say oh I tried.
"This will go as far as it can given our legal system, that might be our Supreme Court, it just depends on the way our laws are fashioned."
Mr Mulvaney added that regardless of the outcome, it will be difficult to unite the country after the election.
He said: "Donald Trump did not cause the division in the country, the division in the country caused Donald Trump.
"I doubt that either of these men has the ability to unite that nation
"It's not in the president's nature, he's not a conciliatory type of guy, he sees the world in winners and losers
"Joe Biden might have a personality that is more inclined to be conciliator but he leads a party now that is absolutely the furthest from that."
You can listen to the full interview here: