US Supreme Court Justice Clarence Thomas has said he believed luxury trips taken with a billionaire Republican donor were "not reportable".

A ProPublica report earlier this week said Mr Thomas had accepted vacations from real estate mogul Harlan Crow nearly every year for two decades.

Supreme Court justices are required to file annual disclosures of gifts.

Mr Thomas said that he had been led to believe that "this sort of personal hospitality" did not apply.

According to ProPublica, the trips included several on Mr Crow's luxury yacht and private plane, as well as a week spent every summer in the Adirondack mountains.

One trip, to Indonesia in 2019, may have cost as much as $500,000 (£402,725), according to the non-profit news website.

In a statement on Friday, Mr Thomas said that he had sought "guidance from my colleagues and others in the judiciary" and was told that "that this sort of personal hospitality from close personal friends, who did not have business before the Court, was not reportable".

"I have endeavoured to follow that counsel throughout my tenure, and have always sought to comply with the disclosure guidelines," the statement added.

Mr Crow, a leading donor to Republican and conservative political causes in the US, told ProPublica that the trips with Mr Thomas and his wife Ginni Thomas were "no different from the hospitality that we have extended to many other dear friends."

"Justice Thomas and Ginni never asked for any of this hospitality," the statement said.

The statement from Mr Crow added that court cases were "never discussed" on the trips and that he is unaware of any attempts by other guests "lobbying or seeking to influence Justice Thomas on any cases".

"I would never invite anyone who I believe had any intention of doing that," he said. "These are gatherings of friends."