Feb 22 (Reuters) - Austria's financial regulator FMA has been investigating Raiffeisen Bank International over anti-money-laundering failures, the Austrian bank said on Thursday in its annual report.

The investigation is focused on the so-called know-your-customer rules, the bank said, referring to a key safety guard to prevent money laundering.

It comes as the group, the largest Western bank in Russia, is also under investigation by the United States' sanctions authority - the Treasury Department's Office of Foreign Assets Control.

The Austrian inquiries concern payments involving Russia and data revealed by the International Consortium of Investigative Journalists in a project dubbed Cyprus Confidential, said a person with direct knowledge of the matter.

A spokesperson for the bank said it had been informed of the regulator's findings in January and that it would appeal any penalty, although none had yet been handed down. "This relates to old payments up to 2020," he said.

The regulator is examining payments involving three customers, processed between 2017 and 2020, in an inquiry that could lead to fines, the bank said in the annual report, adding that it had been informed of the inquiry in January 2023.

The bank said that the Austrian regulator believed it had "failed to fully comply with its administrative obligations".

The bank also gave an update on the U.S. inquiry, describing OFAC's attempts "to clarify payments business ... maintained by RBI with U.S. correspondent banks in light of the developments related to Russia and Ukraine".

"A breach of U.S. sanctions may ... result in fines, the freezing of accounts or the termination of business relationships with U.S. correspondent banks," it wrote. (Reporting By John O'Donnell; Editing by Emelia Sithole-Matarise)