The move cast a shadow of legal uncertainty over the deal and drew criticism from the EU's executive body.

In a vote in Strasbourg, France, 334 lawmakers narrowly approved sending the EU-Mercosur agreement to Europe’s top court to rule on whether it is in line with the bloc’s treaties. 324 voted against the move.

The EU's agreement with South American trade bloc Mercosur aims to create the world’s largest free trade area. It has received support from the European Commission and most member states, but is facing opposition from France, Poland, and EU farmers groups.

Hundreds of farmers with tractors gathered outside the parliament building ahead of Wednesday's vote, and then erupted in celebration as the result came in.

The Court of Justice will now have to assess the legal challenge, a process that could delay and even derail a deal seen as a cornerstone of a Brussels push to open up new markets.