US President Donald Trump on Thursday pulled his embattled nominee for the country's surgeon general, whose confirmation was stalled as lawmakers voiced concern including over her views on vaccines.

Trump said he would offer a third nominee for the post, Nicole Saphier -- a radiologist and director of breast imaging at a branch of Memorial Sloan Kettering Cancer Center. Saphier also frequently appears as a medical expert on Fox News.

Trump said Saphier "makes complicated health issues more easily understood by all Americans."

Surgeon generals are nominated by the US president and can play key roles in communicating public health information, though their actual power is limited.

Trump's previous pick, Casey Means -- a close ally of health chief and vaccine skeptic Robert F. Kennedy Jr -- faced opposition from lawmakers from both parties needed to confirm her appointment.

Means was a vocal critic of the "medical establishment." She graduated from Stanford's medical school but left her subsequent surgical residency, instead becoming a wellness influencer and health products entrepreneur.

She pushed concepts popular with the Make American Healthy Again (MAHA) movement, notably that Americans are overmedicalized.

Lawmakers grilled Means over her views on vaccines as well as her medical experience.

Trump said Thursday that "Casey will continue to fight for MAHA on the many important Health issues facing our Country, such as the rising childhood disease epidemic, increased autism rates, poor nutrition, over-medicalization, and researching the root causes of infertility, and many other difficult medical problems."

He also struck out at Senator Bill Cassidy of Louisiana, the chairman of the Senate Health Committee that questioned Means, and urged the Republican lawmaker's constituents to vote him out of office in an upcoming primary.

Cassidy, a medical doctor, cast the key vote to confirm the controversial nomination of Kennedy as health secretary.