Fairfax Financial Holdings’ RiverStone runoff subsidiary has signed an agreement with Brit Group to buy all the outstanding shares of Brit Insurance Limited (BIL) of London, England for an undisclosed sum.

According to the insurer, the deal is expected to complete in the fourth quarter of 2012, after obtaining concerned regulatory approval.

As per the agreement settled, RiverStone will buy BIL at a discount to its book value, adjusted for certain pre-closing dividends and the purchase price for BIL is expected to be approximately $300m, which is subject to certain adjustments at closing.

Commenting on the deal, Fairfax chairman and chief executive officer Prem Watsa said, "We think that this is an excellent acquisition by Nick Bentley and his experienced team at RiverStone. We continue to look for opportunities to grow profitably in the runoff area."

As of 31 March 2012, BIL’s gross and net reserves were nearly $1.9bn and $1.3bn, respectively, its cash and invested assets were approximately $1.9bn, and its book value was almost $530m.

Fairfax, a financial services holding firm through its subsidiaries, offers property and casualty insurance and reinsurance and investment management services.