McCrory issued the veto threat one day after state Health and Human Services Secretary Aldona Wos said no legislator had asked her department to review the bill, which calls for the DHHS to rewrite regulations for abortion clinics that would impose stricter rules similar to those for walk-in clinics.
Such rules would force 16 abortion clinics in the state to close, Wos said.
DHHS and the governor agreed with provisions such as allowing healthcare providers opposed to abortion to opt out, she said. However, Wos said, other parts of the bill "are far more complex and require further discussion and clarity prior to passage to ensure they are medically sound, safe and legal."
Wos said she needed additional inspectors to ensure safety at the clinics. Her department currently has 10 inspectors who are responsible for checking on hundreds of medical facilities across the state.
McCrory said the bill must undergo "significant changes" before he will sign it, The (Raleigh) News & Observer reported.
Shortly after McCrory's threat, Republicans added less-restrictive abortion provisions to an unrelated bill, The Washington Post reported. Supporters of the measure say it addresses McCrory's concerns, the newspaper said.
McCrory had promised during his campaign he would not allow additional restrictions on abortion. He said he opposed the bill in its current form, noting there was "a fine line between safety measures and restrictions."