WASHINGTON (AP) — The Trump administration's Medicare chief is slamming "Medicare for All," the proposal from Vermont Sen. Bernie Sanders for a national health care plan that would cover all Americans.

Speaking in San Francisco on Wednesday, Medicare administrator Seema Verma says putting millions more people on Medicare would undermine care for seniors.

"In essence, Medicare for All would become Medicare for None," Verma told an audience at the Commonwealth Club.

She says it would "run the risk of depriving seniors of the coverage they have worked their entire lives to receive."

There was no immediate response from Sanders' office, but in the past he has defended his plan by saying it would improve benefits for seniors — for example, by adding coverage for vision, routine dental care and hearing aids.