European Council President Donald Tusk said he and Canadian Prime Minister Justin Trudeau still believed they could hold a joint summit in Brussels on Thursday despite Belgium's incapacity to sign an EU-Canada free trade deal.
Belgian Prime Minister Charles Michel earlier told Mr Tusk, who chairs meetings of EU leaders, that Belgium could not approve the trade deal because of opposition from its French-speaking authorities.
The summit was designed for the EU and Canada to sign the agreement.
"Together with PM @JustinTrudeau, we think Thursday's summit still possible," Mr Tusk said in a tweet. "We encourage all parties to find a solution. There's yet time."
Mr Charles earlier said that Belgium is unable to sign off on the after Wallonia and other regional administrations refused to give the federal government the go-ahead.
"We are not in a position to sign CETA," Mr Michel said after brief talks with Belgium's regional leaders in Brussels broke up without an accord.
"The federal government, the German community and Flanders said 'yes.'
Wallonia, the Brussels city government and the French community said 'no','" he added.
The trade pact is officially known as the Comprehensive Economic and Trade Agreement and the European Union requires approval from all 28 member states to go ahead.
In turn, under Belgium's devolved power structure, Mr Michel needs clearance from all of the country's regional governments to give his assent.
Mr Tusk yesterday called for an answer from Belgium by late today so he would be able to tell Mr Trudeau to come or not.
Wallonia regional leader Paul Magnette said earlier as he left the talks that he could not endorse the accord under such pressure.
"Prime Minister (Michel) told us that the head of the European Council Donald Tusk wanted an answer from us today, yes or no," Mr Magnette said.
"It is evident that in the current circumstances, we cannot give a 'yes' today," he said.
CETA would link the European Union's single market of 500 million people, the world's biggest, with the tenth largest global economy.
Supporters say it will provide jobs and growth but opponents argue it will undermine EU consumer and environmental standards and give multinationals corporations too much say.
Belgium has progressively decentralised its political structure in a bid to end crippling squabbles between Dutch-speaking Flemings and French-speaking Walloons.
Wallonia accounts for more than half of Belgium's territory and about 3.5 million of its 10 million population.
Once the country's economic dynamo, the region was badly hit by the closure of steel plants and coal mines at the end of the last century, and again after the 2008 financial crisis.
