The US Supreme Court’s conservative majority appeared sceptical of President Joe Biden’s $400bn student loan relief programme, possibly paving the way for one of the administration’s flagship economic policies to be struck down later this year.

In oral arguments before the court on Tuesday, conservative justices who hold a majority on the nine-member body questioned whether Biden had the power to wipe out student debt for some borrowers as well as whether the measure was fair. They also suggested that such a step should have been adopted by Congress through legislation, rather than executive action from the White House.

“I think most casual observers would say if you’re going to give up that much money, if you’re going to affect the obligations of that many Americans on a subject that is of great controversy, they would think that’s something for Congress to act on,” Chief Justice John Roberts said.