King Charles III will "stand ready to support" the police if approached about accusations that his brother, ex-prince Andrew, may have passed sensitive reports to Jeffrey Epstein when he was a UK trade envoy, Buckingham Palace said Monday.

"The King has made clear... his profound concern at allegations which continue to come to light in respect of Mr (Andrew) Mountbatten-Windsor's conduct," the palace said in a statement, after UK police said they were "assessing" the misconduct allegations arising from files related to the late American sex offender Epstein.

"While the specific claims in question are for Mr Mountbatten-Windsor to address, if we are approached by Thames Valley Police we stand ready to support them as you would expect."