UnitedHealth Group continues to expand its Optum health services division, entering into an agreement to handle non-clinical operations at one of California's largest physicians groups.

The Minnetonka-based company confirmed Wednesday that Optum has entered into a "strategic relationship" with Monarch HealthCare, an Irvine-based group of more than 2,300 independent physicians. Terms of the deal were not disclosed.

In the past year, Optum has started managing two smaller physicians' groups in southern California, AppleCare Medical Group and Memorial HealthCare Independent Practice Association.

"Optum shares Monarch HealthCare's commitment to bringing patients, physicians, hospitals and health care payers closer together in the mission to increase the quality and affordability of care," Optum's CEO Larry Renfro said in an e-mailed statement.

Optum has a workforce of about 30,000 nationwide and 4,000 in the Twin Cities. The division recently moved into a new headquarters in Eden Prairie. It is a fast-growing and profitable arm of UnitedHealth Group that is separate from the company's insurance division.

Optum operates in three health care services areas -- wellness and behavioral services, information and research, and prescriptions.

Monarch is one of California's 10 largest independent practice associations. In a statement, CEO Bart Asner said that the agreement with Optum will "help support our physicians in providing high-quality, cost-effective patient care."

Jackie Crosby • 612-673-7335