MONTREAL -- Quebec Premier Francois Legault posted a letter to Prime Minister Justin Trudeau Saturday morning saying he will use all means necessary - including the notwithstanding clause - to defend French in the province.

Legault posted a message of "accomplishment" on his Facebook page heralding the work of Minister Responsible for the French Language Simon Jolin-Barrette and connecting a direct line between his government and the 1977 Parti Quebecois government of Rene Levesque that adopted Bill 101.

"This law will be the strongest action to protect our language, since the passage of Bill 101 in 1977," Legault wrote. "Forty-four years later, a nationalist government takes over from the Levesque government with a new Bill 101, I say in all modesty."

Legault said he would use all means available to ensure French in Quebec is adequately protected "including the notwithstanding clause."

The notwithstanding clause (or override clause) is part of the Canadian Constitution, and allows provincial or territorial governments to temporarily override or bypass certain rights in the Canadian Charter of Rights and Freedoms.

Jolin-Barrette tabled the long-awaited Bill 96 - An Act respecting French, the official and common language of Québec - on Thursday, which immediately set off a wave of media attention, controversy and concern particularly among English-speaking communities in the province.

Legault wrote of his responsibility in keeping French alive on a "massively English-speaking continent."

"French in Quebec will always be threatened," he said. "And every generation has a responsibility to ensure their survival. It's our turn to carry the torch, our turn to protect our tongue with pride."

In Legault's letter to Trudeau, he writes that Quebec is the only French-speaking state in North America and that "protecting the French language is one of the most important responsibilities or even the greatest responsibility of a Quebec premier."

The Caribbean state of Haiti, which is also in North America, lists French and Haitian Creole as the state's official languages.

Canada's 2016 census reports just under 8 million people in the country as French-speaking (22.8 per cent) and just over 6.2 million people (17.9 per cent) are bilingual.

Legault said that despite efforts in recent decades, French-speaking numbers have declined, and that reforms to Bill 101 were needed including amending the province and country's constitutions to say that Quebec is a distinct nation and that "French is its official language."

The Quebec premier also acknowledged that the former Bill 101 caused controversy in the rest of Canada when it was passed, but said that since then "Canadian politicians and observers have not hesitated to call it a great Canadian law."

He also said that former prime minister Stephen Harper had a motion passed in the House of Commons recognizing the Quebec nation.

Legault also wrote that the bill respects English-speaking communities' rights and institutions in Quebec.

"My wish is that this major action in favour of our French language brings Quebecers together and their collective pride," he wrote.