The US Supreme Court has ruled that President Donald Trump can dismiss a top official on the Federal Trade Commission.

In the 6-3 ruling, the justices sided with Trump, allowing him to fire Democratic Commissioner Rebecca Slaughter from her post while legal challenges continue.

It has also agreed to revisit a nearly century-old legal precedent that shields independent agencies set up by Congress from presidential interference.

Justice Elena Kagan, writing for the dissenting liberal justices, warned that the ruling allows the president to take charge of institutions Congress had intended to protect from partisanship.

"Congress, as everyone agrees, prohibited each of those presidential removals," Justice Elena Kagan wrote in her dissent. "Yet the majority, stay order by stay order, has handed full control of all those agencies to the President."

"He may now remove - so says the majority, though Congress said differently - any member he wishes, for any reason or no reason at all. And he may thereby extinguish the agencies' bipartisanship and independence, " Justice Kagan added.

The Supreme Court's Monday ruling said the justices would hear arguments in December on overturning a 1935 decision that allowed Congress to set up independent agencies insulated from political interference.

In the 90-year-old ruling known as Humphrey's Executor, the court sided with another FTC commissioner who was fired by Franklin D Roosevelt. The justices then ruled that commissioners could be removed only for misconduct or neglect of duty.

The FTC, which enforces consumer protection, typically has five commissioners - three from the president's party and two from the opposing party.

Slaughter and Alvaro Bedoya, two Democratic members of the FTC, were fired by Trump in March.

A federal judge ruled in July in favour of Slaughter, declaring her dismissal "unlawful" under the longstanding precedent. Bedoya later resigned, but Slaughter continued her legal battle.

Earlier this month, the Supreme Court issued a temporary order permitting Trump to proceed with the dismissal as the justices considered whether to take up the case - a move now confirmed by Monday's decision.

Separately, the court is also considering the Trump administration's request to remove Lisa Cook as a Federal Reserve governor.

Cook was fired in August after the administration accused her of committing mortgage fraud.

The governor has denied any wrongdoing, and a federal court sided with her, stating the president did not have the power to remove her.