Clifford Chance's head of insolvency, Ashley Booker, has handed in his notice and is no longer working at the firm after "discussions" with the partnership on which Clifford Chance refuses to comment.
Speculation about the reasons behind his departure are rife but Booker, speaking from his Wimbledon home, denied rumours of an investigation by the firm.
He said he had not taken part in one: "I don't know what investigation Clifford Chance may or may not have carried on into anything."
He added: "I have tendered my resignation with effect from 31 October having had discussions with people at Clifford Chance. It's for entirely personal reasons which I am not prepared to discuss with you."
Senior partner Keith Clarke refused to comment and, when pressed, hung up the phone.
The resignation is a severe blow to the firm's seven-year-old insolvency practice which had been seen as one of the top five in the City.
Leading partner Sandy Shandro left the firm last month after what is understood to be a personality clash with Booker. Prior to that, partner Andrew Wilkinson resigned last summer.
Insolvency partner Mark Hyde was sent to the Hong Kong office last month, leaving only one partner, David Steinberg.