Canada and the European Union say they remain hopeful a landmark free trade deal can go ahead despite three Belgian regions led by Wallonia blocking it.
European Council President Donald Tusk said it was still possible Ceta could be signed as planned and Canada's trade minister said the deal was "not dead".
But Belgium has said it cannot back the deal because three French-speaking parts of the country oppose it.
Ceta needs the support of all 28 EU nations before it can be approved.
It is the EU's most ambitious free trade deal to date, and has been in the pipeline for seven years. The other 27 EU governments want to sign the agreement.
However, hopes it could be signed on Thursday appeared to be dashed on Monday when Belgian Prime Minister Charles Michel said he did not have the unanimous approval of his country's federal, regional and community bodies.