Canada's top court has refused to look at whether Quebec's controversial ban on religious symbols should be suspended until the case is heard on its merits.

Civil rights groups had filed an appeal to the Supreme Court of Canada in January after Quebec's Court of Appeal dismissed a request to suspend portions of the law, known as Bill 21, pending a ruling on its constitutionality.

The Supreme Court did not give a reason Thursday for denying to hear the case, as is its usual practice.

In a 2-1 decision, the appeals court said in December the law should be allowed to stand until the challenges are heard in Quebec Superior Court.

That's the decision the groups sought leave to appeal. If the Supreme Court judges had chosen to hear the appeal, they would have had to decide whether Quebec must suspend the law while the challenges are heard.

The law bans public school teachers, government lawyers and police officers, among other civil servants, from wearing religious symbols at work.

4 lawsuits

It is being challenged in four separate lawsuits, three of which are expected to be heard together in October.

"We promised to defend Canadian civil liberties and we will continue to keep that promise," said Mustafa Farooq, executive director of the National Council for Canadian Muslims, one of the groups that filed the appeal.

"This decision, while not the one we were hoping for, is not the end of the battle."

Noa Mendelsohn Aviv, a director with the Canadian Civil Liberties Association, said Bill 21 created "unnecessary division and economic hardship."

"While we are deeply disappointed in this result, our main challenge of the law still lies ahead."

Constitutional arguments

The two groups have also filed a challenge in Quebec Superior Court to the law itself, arguing it is unconstitutional.

The application to the Supreme Court had raised two major issues: whether there has to be a "clear case of unconstitutionality" as the standard for a law to be suspended while it is further challenged in the courts, and whether the notwithstanding clause can prevent a law from being stayed.

The Quebec government invoked the notwithstanding clause in a bid to restrict challenges to the law's constitutionality.

The applicants have argued the legislation is beyond Quebec's power to create since "regulating religion for a moral purpose falls under federal jurisdiction to adopt criminal laws."

They say it is "impermissibly vague," excludes people from public careers and is sexist.