(CNN) -- France's law banning the burqa and other Islamic face coverings in public places is legal, top constitutional authorities in France ruled Thursday, clearing the final hurdle before the ban goes into effect.

The ban passed both houses of the French legislature by overwhelming margins earlier this year, and is scheduled to come into effect in the spring.

The law imposes a fine of 150 euros ($190) and/or a citizenship course as punishment for wearing a face-covering veil. Forcing a woman to wear a niqab or a burqa will be punishable by a year in prison or a 15,000-euro ($19,000) fine, the government said, calling it "a new form of enslavement that the republic cannot accept on its soil."

Lawmakers also cited security reasons for forbidding people from covering their faces in public.

The French Constitutional Council said the law did not impose disproportionate punishments or prevent the free exercise of religion in a place of worship, finding therefore that "the law conforms to the Constitution."

A panel of French lawmakers recommended a ban last year, and lawmakers unanimously passed a non-binding resolution in May calling the full-face veil contrary to the laws of the nation.

"Given the damage it produces on those rules which allow the life in community, ensure the dignity of the person and equality between sexes, this practice, even if it is voluntary, cannot be tolerated in any public place," the French government said when it sent the measure to parliament in May.

French people back the ban by a margin of more than four to one, the Pew Global Attitudes Project found in a survey earlier this year.

Some 82 percent of people polled approved of a ban, while 17 percent disapproved. That was the widest support the Washington-based think tank found in any of the five countries it surveyed.

Clear majorities also backed burqa bans in Germany, Britain and Spain, while two out of three Americans opposed it, the survey found.

Amnesty International has repeatedly urged France not to impose the ban, saying it violates European human rights law.

The ban pertains to the burqa, a full-body covering that includes a mesh over the face, and the niqab, a full-face veil that leaves an opening only for the eyes.

The hijab, which covers the hair and neck but not the face, and the chador, which covers the body but not the face, apparently are not banned by the law.

However, a 2004 law in France bans the wearing or displaying of overt religious symbols in schools -- including the wearing of headscarves by schoolgirls.

The Pew Forum on Religion & Public Life estimates that France has about 3.5 million Muslims, or about 6 percent of the population.

France does not keep its own statistics on religious affiliation of the population, in keeping with its laws requiring the state to be strictly secular.

CNN's Alanne Orjoux, Pierre Meilhan and Saskya Vandoorne contributed to this report.