Warburg Pincus is believed to be on the lookout for buyers for selling its 50.12% stake in BPO firm WNS Global Services. WNS may fetch a valuation of around $800 million providing Warburg with an exit payout of $400 million, according to a report in the Economc Times.

Warburg had paid $40 million when it acquired a 64% stake in WNS from British Airways in 2002. The PE firm is reportedly in talks with Bain capital and the Blackstone Group despite speculation that IT services majors like Cognizant and even some mid-tier firms could be interested in pursuing the deal.

A due diligence process is likely to be kicked off in the next couple of days, the paper reported, emphasising that the process was in its early stages.

Merrill Lynch is believed to be advising Warburg on the possible stake sale.