SINGAPORE, June 24 (Reuters) - Singapore conglomerate Keppel Corp and Sembcorp Marine are in the process of kicking off talks to explore combining their struggling offshore and marine (O&M) businesses, two sources familiar with the matter said on Thursday. The sources declined to be identified as they were not authorised to speak to media. Trading in shares of Keppel and Sembcorp Marine were halted on Thursday pending announcements. Keppel declined comment while there was no immediate response from Sembcorp Marine to a Reuters query. (Reporting by Anshuman Daga, additional reporting by Aradhana Aravindan; Editing by Himani Sarkar) Our Standards: The Thomson Reuters Trust Principles.