Washington DC - President Joe Biden on Friday commuted the sentences of nearly 2,500 people convicted of non-violent drug offenses in what the White House called the largest single-day act of clemency in US history.

Those whose sentences were commuted were serving "disproportionately long sentences" compared to what they would receive today, Biden said in a statement.

He called the move "an important step toward righting historic wrongs, correcting sentencing disparities, and providing deserving individuals the opportunity to return to their families."

"With this action, I have now issued more individual pardons and commutations than any president in US history," Biden said, adding that he may issue further commutations or pardons before he hands over power to President-elect Donald Trump on Monday.

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Biden commuted the sentences of nearly 1,500 people and pardoned 39 others last month.

Among those pardoned in December was Biden's son Hunter, who was facing a possible prison sentence after being convicted of gun and tax crimes.

"These final clemency actions will forever define President Biden’s legacy on justice," FWD.us Executive Director Zoë Towns said in a statement Friday. "Too often, our criminal justice reforms only apply to the law going forward, leaving behind the very people and injustices that moved us to change. For example, we reached consensus long ago that the crack/powder cocaine sentencing disparity could not be defended on public health or public safety grounds and that it fueled already stark racial disparities. Yet many are still incarcerated on sentences that could not be handed down today."

“We’re grateful for President Biden’s final acts of leadership in delivering relief, justice, and mercy to thousands and, importantly, calling attention to the harms of extreme sentencing and the benefits of reform," she added.

Biden has, meanwhile, reportedly been debating whether to issue blanket pardons for some allies and former officials amid fears they could be targeted for what Trump has previously called "retribution."

The outgoing president faces overwhelming calls from Native communities and allies to grant clemency to Leonard Peltier, the US' longest-held Indigenous political prisoner.

In December, Biden commuted the death sentences of 37 of the 40 people on federal death row. Three men were excluded from the move: one of the 2013 Boston Marathon bombers, a gunman who murdered 11 Jewish worshippers in 2018, and a white supremacist who killed nine Black churchgoers in 2015.

Trump has indicated that he will resume federal executions, which were paused while Biden was in office.