A British group bought a Michigan insurance firm.

Prudential Corp. agreed to buy Lansing-based Jackson National Life Insurance Co. for $608 million, gaining a foothold in the U.S. market. Prudential, which is not connected with the Prudential Insurance Co. of America, has been considering a move into U.S. life insurance for several years but was waiting for the right partner, the British firm said. The $51-per-share offer requires approval by Jackson shareholders and regulatory authorities. Prudential owns one of the United Kingdom’s largest life insurance companies.