By Andrew Chung and John Kruzel

WASHINGTON Conservative U.S. Supreme Court Justice Clarence Thomas, under scrutiny over revelations that he did not disclose luxury trips paid for by a billionaire Dallas businessman, received an extension to file his annual financial disclosure, the court said on Wednesday.

Supreme Court justices, like some other senior government officials, are required under U.S. law to file annual financial disclosures that report outside income and gifts.

Fellow conservative Justice Samuel Alito also was granted an extension, according to the court, while the other seven justices filed theirs.

The court has come under criticism from many Democrats in Congress in recent months over ethics issues involving some of its justices, in particular Thomas.

The news outlet ProPublica reported in April that Thomas has for decades accepted luxury trips from businessman and Republican donor Harlan Crow, including on a private jet and superyacht, without publicly disclosing them. It also detailed real estate transactions involving Thomas and Crow.

Food and other "personal hospitality" such as lodging at an individual's residence is generally exempt from disclosure, although the Judicial Conference, the policymaking body for the broader federal judiciary, has tightened its regulations related to the exemption, including requiring transport by private jet to be disclosed.

Thomas, the longest-serving of the justices, said in response to the ProPublica report that he had been advised that under the previous rules he was not required to report hospitality from "close personal friends" but intended to follow the new guidelines.

In 2016, Thomas disclosed in his filing that Crow had given him a bronze bust of 19th century slavery abolitionist and writer Frederick Douglass, estimated to be worth $6,500.

Separately, the news outlet Politico has reported that conservative Justice Neil Gorsuch failed to disclose the buyer of a Colorado property in which he had a stake - the chief executive of a major law firm whose attorneys have been involved in numerous Supreme Court cases.

The recent revelations have reignited calls, particularly from Democrats, for ethics reform at the Supreme Court.

Supreme Court justices are not bound like other federal judges by a code of conduct adopted by the Judicial Conference that includes avoidance even of the "appearance of impropriety." Chief Justice John Roberts has said Supreme Court justices consult that code in assessing their own ethical obligations.

The Democratic-led Senate Judiciary Committee last month explored the possibility of pursuing legislation to impose ethics standards on the justices. Roberts declined an invitation to testify at the hearing and none of the justices appeared. Republicans on the panel generally opposed imposing ethics regulations but some urged the justices to act themselves to improve transparency at the court.

Roberts is due to collect a salary of $298,500 this year, slightly higher than the $285,400 paid to the other eight justices. In keeping with annual salary adjustments prescribed by federal law, these amounts represent increases from 2022, when Roberts was paid $286,700 and the others made $274,200.

(Reporting by Andrew Chung in New York and John Kruzel in Washington; Editing by Will Dunham)