US President Donald Trump has pardoned his former campaign chairman Paul Manafort, who was convicted as part of Robert Mueller’s investigation into Russian interference in the 2016 US election.

Mr Trump also pardoned his associate Roger Stone and Charles Kushner, a real estate developer and the father of Mr Trump’s son-in-law.

It was the second wave of pardons Mr Trump has issued in two days and came just after Mr Trump arrived in Palm Beach, Florida, for the holiday season.

In total, he issued on Wednesday (local time) full pardons to 26 individuals and commuted part or all of the sentences of an additional three people.

Paul Manafort was convicted following an investigation into Russian interference in the 2016 election. Photo: AP

Mr Trump’s pardoning of Manafort spared the long-time Republican operative from serving the bulk of his seven-and-a-half-year jail term.

Manafort, 70, was among the first in Trump’s inner circle to face charges brought by Special Counsel Robert Mueller as part of his probe into Russian interference in the 2016 presidential election.

Mr Manafort thanked Mr Trump and lavished praise on the outgoing president, declaring that history would show he had accomplished more than any of his predecessors.

Tweet from @PaulManafort

Stone was convicted in November 2019 by a Washington jury of lying under oath to lawmakers also investigating Russian interference in the 2016 election.

Roger Stone, a former campaign adviser for President Donald Trump, has been granted a pardon. Photo: AP

Mr Trump commuted his sentence in July, a day before Stone was due to begin serving a term of three years and four months.

Kushner, father of Trump son-in-law Jared Kushner, was sentenced to two years in jail after pleading guilty in 2004 to 18 counts of tax evasion, witness tampering and making unlawful campaign donations.

In an unusual twist, the man who prosecuted Charles Kushner was Chris Christie, now the former governor of New Jersey, who also has served as an adviser to Mr Trump.

Mr Christie was quoted by CNN as saying Charles Kushner’s case was “one of the most loathsome, disgusting crimes” he prosecuted.

Mr Trump and the elder Mr Kushner know each other from real estate circles.

Their children were married in 2009.

The pardons come soon after Mr Trump vetoed a massive US defence policy bill, worth $US740 billion ($A980 billion) in military programs and construction.

-with agencies