US President Joe Biden was unveiling new plans Monday to reduce student loan debt for millions of Americans, in a fresh bid to win over young voters who will be crucial in Novembers election.

The Democrats proposals come after his initial, bigger ambitions to cancel several hundred billion dollars of debt were struck down by the conservative-dominated US Supreme Court in June.

The plans, if implemented, would provide debt relief to over 30 million Americans, the White House said in a statement ahead of a speech by Biden in Madison, Wisconsin.

The plans would wipe out accrued interest for 23 million borrowers, cancel all student debt for four million others, and give at least $5,000 in debt relief to over 10 million borrowers, it said.

It means breathing room, it means freedom from feeling like your student loan bills compete with basic needs, like grocery or health care, Education Secretary Miguel Cardona told reporters.

White House Press Secretary Karine Jean-Pierre added that Biden would use every tool available to cancel student debt no matter how many times Republican elected officials tried to stand in his way.

The new plans were entirely consistent with the court decision last year, which the White House had studied carefully, a senior administration official said.

Younger voters helped Biden beat Republican then-president Donald Trump in the 2020 election, and he will need the key demographic on side to come from behind in the polls this year.

Bidens student loan policy has been a key part of that, but it was derailed when his plan to cancel more than $400 billion of debt was struck down.

The Supreme Court features three judges appointed by Trump while in office and has moved sharply to the right in recent years, notably with last years landmark overturning of the federal right to abortion.(AFP)