In a brief interview on Friday, Mr. Mims said that he was still discussing with legislative lawyers just how quickly the state was allowed to act.

For the clinic, it may simply be a matter of facing the threat of closing in either days or weeks, if the physicians are not granted admitting privileges. State officials are expecting a lawsuit if that happens.

Nine other states have local admitting requirements for abortion providers, according to the Guttmacher Institute, a research group focused on sexual and reproductive health and rights. But in none of those states did such a rule effectively end abortion, and that will be the crux of the legal fight. Mississippi political leaders have said the law is intended to safeguard the health of women, but they have not been circumspect about the larger goal.

“This is the only state where the proponents are this honest about what exactly their motivation is,” said Michelle Movahed, a lawyer with the Center for Reproductive Rights, which is representing the clinic.

One state legislator, Bubba Carpenter, was videotaped in May telling a gathering of Republicans that with the new law the Legislature had “literally stopped abortion in the state of Mississippi.”

Representative Mims said that the law does not outlaw abortion; the idea, he said, was to require physicians at the clinic to be able to follow their patients to a local hospital if complications arise. But, he added, “if this abortion clinic is closed, I think it’s a great day for Mississippi.”

Mississippi’s abortion rate is already low, in part because of the restrictions currently in place. But it is not surprising that this may be the first state to have no abortion clinic.