By Ahmed Aboulenein WASHINGTON (Reuters) -Dr. Mehmet Oz, the celebrity physician and former Republican U.S. Senate candidate nominated by President Donald Trump to oversee Medicare and Medicaid, is expected to field questions on Friday on industry ties that could create conflicts of interest.

Mehmet Oz, President Donald Trump’s nominee to lead the Centers for Medicare and Medicaid Services, may have “significantly” underpaid Social Security and Medicare taxes in recent years, according to a memo by Democratic staff on the Senate Finance Committee seen by Bloomberg News.

Dr. Mehmet Oz, the celebrity physician who President Donald Trump has nominated to oversee the Center for Medicare and Medicaid Services (CMS), may have potentially underpaid on his Medicare and Social Security taxes.