HSBC Holdings said it was investigating a report of an alleged loss of client data for thousands of its offshore account clients in Jersey but had not been notified of any investigation by tax authorities into the holdings.

British tax authorities are examining details of more than 4,000 UK clients of HSBC in Jersey after a whistle-blower handed them a list of names, addresses and account balances, The Daily Telegraph said on Friday.

"We have not been notified of any investigation in relation to this matter by HMRC or any other authority but, should we receive notification, we will cooperate fully with the authorities," HSBC said in a statement. "We are investigating the reports of an alleged loss of certain client data in Jersey as a matter of urgency."

(Reporting by Steve Slater)