Federal NDP Leader Jagmeet Singh says he's "completely opposed" to Quebec's new and controversial law that would effectively force Muslim women who wear a niqab or burka to uncover their faces to use or provide public services, but he's confident the legislation will be challenged.

The provincial government's Bill 62 on religious neutrality passed a vote Wednesday morning in Quebec's National Assembly.

It bans public workers — including doctors, teachers and daycare workers — as well as those receiving a service from the government from wearing the niqab, burka or any other face covering. It was extended to municipal services, including public transit, in an amendment made in August.

"I'm completely opposed to the bill but I am completely confident in the existing protections that are in place in Quebec that will protect human rights," Singh said, adding he believes the law violates human rights.

"Fundamentally, we can't have the state telling people what to wear, what not to wear."

Quebec Premier Philippe Couillard has acknowledged the law could face a legal challenge, but said it was crafted to be compatible with the Canadian Charter of Rights and Freedoms, as well as the Quebec Charter of Human Rights and Freedoms.

NDP opposed Conservatives' niqab ban

While the niqab and burka are not mentioned in the legislation, Quebec Justice Minister Stéphanie Vallée told CBC earlier this week the bill aims to clearly establish the "neutrality of the state" and is necessary for "communication reasons, identification reasons and security reasons."

Zayneb Binruchd, 21, says she would rather stay home than be forced to take off her niqab to ride a bus. The Quebec government passed Bill 62 on Wednesday. (Sylvain Charest/CBC)

This is not the first time a federal NDP leader has weighed in on the niqab in Quebec.

Singh's predecessor, Tom Mulcair, admitted the NDP's support for a women's right to wear a niqab contributed significantly to the party's crashing fortunes in Quebec during the 2015 election, where a large number of voters backed the Conservative party's pledge to ban the headgear at citizenship ceremonies.

"[The niqab] hurt us terribly. It was measured. I can share with you that the polling we did showed we dropped over 20 points in 48 hours here in Quebec because of the strong stand I took on the niqab," Mulcair told CBC Radio's The House months after the election.

"There were shortcomings in that campaign, and of course I take full responsibility for it."

Trudeau mum on Bill 62

Prime Minister Justin Trudeau, who also went on the offensive over the issue of the niqab ban during the last election, was silent when asked about Bill 62 on his way out of the House following question period Wednesday.

Liberal MP Iqra Khalid, who sponsored a motion known as M-103 to condemn Islamophobia, was brief.

"I think that no person should be told how to dress or how not to dress, and that's about it," she told reporters.

The Quebec Liberals, who hold a majority in the provincial legislature, voted in favour of Bill 62, while all the other parties voted against. The two main opposition parties, the Parti Québécois and Coalition Avenir Québec, have argued the legislation doesn't go far enough.

The bill does provide for the possibility of religious accommodation in certain cases, although it's not clear how that would work.