LONDON, May 29 (Reuters) - Rolls-Royce said on Monday that it was continuing to assist Indian authorities in their investigation against the engine maker, adding that the allegations being probed were disclosed back in 2017 when it paid a fine to UK authorities.

A document showed earlier on Monday that India had filed a graft case against Rolls-Royce and BAE Systems for "criminal conspiracy" in the procurement and licensed manufacturing of 123 Hawk 115 advanced jet trainers.

"Rolls-Royce today is a fundamentally different business. We will not tolerate business misconduct of any sort and are committed to maintaining high ethical standards," a spokesperson for the blue-chip company told Reuters via email. (Reporting by Muvija M and Sinchita Mitra; Editing by Susan Fenton)