OTTAWA – Canada is giving serious thought to ratifying an international labour convention on the right to organize and collective bargaining it has refused to sign since 1949, newly released documents show.

An internal memo from Employment and Social Development Canada says ratifying the key International Labour Organization convention — known as Convention No. 98 — would be one way for Canada to shore up its efforts to ensure the rights of workers are respected overseas.

The memo, prepared for the Privy Council Office last year, says there are limits to Canada’s traditional approach of using free trade agreements to help create a level playing field, protect Canadian businesses from unfair competition and promote human rights.

That strategy “has little impact for countries that have not signed an FTA with Canada and the number of important trading partners that are not subject to bilateral labour obligations is growing,” says the memo, dated Sept. 9, 2015.

“In this context, the need for more effective approaches for influencing workers’ rights internationally is increasingly important.”

The Canadian Press obtained the document under the Access to Information Act.

One of the proposed new strategies, listed under “key options under consideration,” was to sign Convention No. 98.

The Right to Organize and Collective Bargaining Convention, 1949, is one of the fundamental conventions for the International Labour Organization, a United Nations agency that has government, employer and worker representatives.

The convention says all workers shall be protected from anti-union discrimination, such as being forced to give up membership in a union in order to get a job, or getting fired for participating in union activities.

It also enshrines collective bargaining as a right.

Canada is one of 23 countries that have not ratified the convention. The United States is another.

One reason cited in the past is that the Charter of Rights of Freedoms already protects freedom of assembly and association, but that labour laws also fall under the jurisdiction of the provinces, where some categories of employees have been excluded from legislation on collective bargaining.

Labour Minister MaryAnn Mihychuk was not available for an interview Tuesday, but two Canadian employer representatives who attended the International Labour Organization conference in Geneva earlier this month said she spoke of the issue at a lunch meeting there.

Andrew Finlay, chair of the Canadian Employers Council, and Sonia Regenbogen, a Toronto-based lawyer who represents federally and provincially regulated employers, both recalled Mihychuk saying the federal government was considering ratifying the convention.

James Clancy, national president of the National Union of Public and General Employees, said ratifying the convention would send a signal to provincial governments.

“Governments that are anti-worker, anti-union, who have ideas of introducing anti-worker legislation — they simply won’t be able to do it,” Clancy said.

Jamie Knight, vice-president of the Canadian Association of Counsel to Employers, said that since the convention has been around for nearly 70 years, he would want to see the federal government carefully articulate its reason for wanting to do so now.

Knight said he is also concerned ratifying the convention would cause further legal confusion in the wake of recent Supreme Court decisions on labour relations, such as the one granting public service unions the right to strike.

“The waters, we would suggest with respect, are muddy enough at the present time,” Knight said. “In our view the federal government should not go it alone without extensive provincial consultation or agreement.”

Eric Tucker, a labour law professor at Osgoode Hall Law School at York University, said the Supreme Court decisions likely mean ratifying the convention will have little impact on provincial law in Canada.