Sen. Robert Menendez is acknowledging his office contacted U.S. health agencies in a way that would help his biggest political donor, the same doctor whose private jet Menendez used for two personal trips to the Dominican Republic.

Stacy Proebstle, Townsquare Media

But the senator denies he sought to intervene improperly in billing disputes between the doctor and the government.

Menendez, a New Jersey Democrat, says Thursday he contacted the Centers for Medicare & Medicaid Services to ask about billing practices. This was during a dispute between CMS and Salomon Melgen, a longtime friend and donor. The FBI searched Melgen's Florida offices last week.

Menendez says, "The bottom line is, we raised concerns with CMS over policy and over ambiguities that are difficult for medical providers to understand, and to seek a clarification."

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