Athene Holding Ltd., the insurer and annuity seller backed by Apollo Global Management Inc., agreed to acquire a mortgage lender from Fortress Investment Group as it seeks to pick up assets in the U.K.

With the purchase of Foundation Home Loans, Athene will pick up a 3 billion-pound ($4.2 billion) portfolio of mortgages to be managed by Apollo, according to a statement from the Bermuda-based insurer. Terms of the deal weren’t disclosed. Foundation is controlled by Fortress, which is owned by Tokyo-based SoftBank Group Corp.

“This transaction continues our longstanding strategy of working with Apollo to identify and invest in attractive businesses,” Athene Chairman and Chief Executive Officer Jim Belardi said in the statement.

Apollo, the private-equity powerhouse, created Athene in 2009 to generate a stream of cash to invest. It agreed in March to acquire Athene in an all-stock deal that valued the business at about $11 billion. Apollo was already Athene’s biggest shareholder, with the firm and related entities owning a 35% stake.