Russian prosecutors have cleared PwC in Russia of any wrongdoing in auditing Yukos, the bankrupt Russian oil group, PwC said on Wednesday, in an apparent boost to the audit firm nearly four weeks after it said it was withdrawing a decade of Yukos audits.

PwC said on Wednesday it had received a letter from the prosecutors office saying they had found no wrongdoing in PwC’s audits of Yukos. “We are pleased ... the general prosecutor ... has decided not to take any action against PwC Russia, its partners or employees,” it said.