Aon plc (NYSE:AON) is in advanced talks to sell its employee benefits outsourcing unit to Clayton, Dubilier & Rice, Inc. (CD&R) for nearly $4.5 billion, people familiar with the matter said. CD&R reportedly tabled its bid earlier in January 2017 and saw off competition from The Blackstone Group L.P. (NYSE:BX) in the auction. However, talks with Aon are ongoing and a transaction is not guaranteed, Reuters noted.

Aon hopes to announce a deal by February 10, 2017 when it plans to report fourth-quarter earnings, the sources said. Aon and CD&R declined to comment, while Blackstone did not immediately respond to a request for comment.