A rating agency says the strength of the major U.S. life insurance subsidiaries of Prudential Financial Inc. is growing.

Fitch Ratings, Chicago, says it is increasing its insurance financial strength ratings for the life subsidiaries of Prudential, Newark, N.J., 1 notch and assigning the new ratings a stable outlook.

Prudential has been doing well, has plenty of capital to pay its debts, and has done a good job of integrating recent acquisitions, according to Fitch.

Fitch has increased the insurance financial strength ratings of units such as Prudential Insurance Company of America, PRUCO Life Insurance Company, American Skandia Life Assurance Corp. and Prudential Retirement Insurance & Annuity Company to AA, from AA minus.