More than 100 French left-wing lawmakers decided on Tuesday to appeal to the country's Constitutional Council to block a contentious free trade deal between the European Union and Canada.

Supporters of the Comprehensive Economic and Trade Agreement (CETA) say it will boost economic growth and jobs on both sides of the Atlantic. But opponents say it will lead to a race to the bottom in labour and environmental standards and allow multinational corporations to dictate public policy.

In a statement, 106 members of France's National Assembly said the accord implied a transfer of sovereignty by signatory countries "beyond what they agreed upon in favour of the EU".

European Parliament lawmakers backed the CETA by a comfortable majority last week, meaning that large parts of the deal, notably tariff reduction, will finally enter into force some eight years after negotiations began.