WASHINGTON, June 23 (Reuters) - U.S. health secretary

Robert F. Kennedy Jr. met with major health insurers on Monday,

extracting pledges that they will take additional measures to

simplify their requirements for prior approval on medicines and

medical services.

Insurers including UnitedHealth Group Inc's ( UNH )

UnitedHealthcare, CVS Health Corp's ( CVS ) Aetna, Cigna Group ( CI )

, Humana Inc ( HUM ), Blue Cross Blue Shield Association

and Kaiser Permanente met with Kennedy and Centers for Medicare

and Medicaid Services Administrator Mehmet Oz, the Department of

Health and Human Services said in a statement.