The Republican-controlled U.S. Senate voted on Thursday 53-45 along party lines to confirm Dr. Mehmet Oz, the celebrity physician nominated by President Donald Trump, to oversee government health insurance programs Medicare and Medicaid.

As administrator for the Centers for Medicare and Medicaid Services, Oz, who has never held public office, will oversee a wide-reaching agency with annual spending of $2.6 trillion that oversees health insurance for more than half of Americans.

He would head Medicare, the federal health insurance program for people aged 65 or older or who have disabilities, oversee Medicaid, the state-based health insurance program for low-income people, and the Children's Health Insurance Program, known as CHIP, for low-income children and pregnant women.

He would also run the main program for income-based government-subsidized health insurance under the Affordable Care Act, also known as Obamacare.

Collectively these programs provide coverage for almost 172 million people, government data shows.

He could be tasked with overseeing significant cuts to Medicaid as Republicans say they hope to cut federal spending in the program. Republicans in the House of Representatives demand $880 billion in Medicaid savings, which they argue could be achieved by rooting out fraud and abuse. Democrats argue it will result in benefit cuts.

Oz, 64, gained national prominence as a cardiothoracic surgeon and television personality, hosting "The Dr. Oz Show" for over a decade.

Republicans control the Senate and have been largely supportive of Oz, who in 2022 ran with Trump's endorsement as the Republican candidate for Senate in Pennsylvania and lost. Republicans have backed nearly all Trump's nominees.