U.S.-based Prudential Financial Inc.'s Prudential Retirement and Aviva PLC's Aviva Life and Pensions U.K. Ltd. agreed to a longevity risk reinsurance transaction.

Under the transaction, Prudential Insurance Co. of America will assume longevity risk for approximately £1 billion in pension liabilities.

The transaction is the first between the two companies, and Tom Ground, managing director of defined benefit solutions at Aviva, said the U.K. company hopes it "is just the start of a longer-term relationship."