Saudi Arabia's crackdown on corruption has spread beyond its borders as regulators in the United Arab Emirates ask UAE banks for information about Saudi citizens detained in the investigation, a possible prelude to freezing their accounts.

The UAE central bank has requested commercial banks and finance companies in the UAE to provide details of the accounts of 19 Saudis, commercial bankers told Reuters yesterday, declining to be named because of the sensitivity of the matter.

Almost all of the 19, including billionaire Prince Alwaleed bin Talal and former National Guard chief Prince Miteb bin Abdullah, are known to be among dozens of senior officials and businessmen detained in the corruption inquiry.

Commercial bankers said UAE authorities had not explained why they wanted the information, but believed the authorities were acting at the behest of the Saudi government, which has said it aims to recover billions of dollars of illicit assets identified in its investigation.

Central bank officials in the UAE, a federation of seven emirates, were not available to comment, and Saudi officials in Riyadh, who have frozen over 1,700 domestic bank accounts as part of the crackdown, did not respond to requests for comment.

The UAE, particularly its most commercially prominent emirate Dubai, is one of the main places where wealthy Saudis park their money abroad.

Meanwhile, Mohammed bin Nayef, Saudi Arabia's ex-crown prince who was removed as next in line to the throne in June, has reportedly become the latest royal family member to be targeted in the kingdom's expanding anti-corruption crackdown.

According to Reuters news agency and the Wall Street Journal, bank accounts linked to Mohammed bin Nayef and some of his immediate relatives were frozen by Saudi authorities.