White Mountains Insurance Group has completed the sale of Sirius International Insurance Group to a subsidiary of CM International Holding.

The estimated gross sale price is $2.59 billion. As a result of the sale it is estimated White Mountains’ adjusted book value per share will gain $90.

CM International Holding is the Singaporean-based investment arm of China Minsheng Investment.

Bermudian-based White Mountains used about $160 million of the proceeds to purchase out of Sirius Group certain assets to be retained the company, including shares of insurer OneBeacon.