Emergency meetings have been taking place in Brussels in an effort to save an EU free trade deal with Canada, blocked by a Belgian region.
European Parliament head Martin Schulz held separate talks with Canadian Trade Minister Chrystia Freeland and the head of Belgium's Wallonia region.
Speaking after her meeting, Freeland said, "It's time for Europe to finish doing its job."
The deadlock has called into question the EU's ability to make trade deals.
After seven years of negotiations on the deal, known as Ceta, talks broke down on Friday.
All 28 EU member states support the Comprehensive Economic and Trade Agreement (Ceta) agreement, which was to be signed next week.
However, exercising its right under the Belgian federal constitution, Wallonia has called for clarity on safeguards to protect labour, environmental and consumer standards.
Freeland said it was clear that the EU could not reach agreement even with Canada, a country that shared European values.
"The ball is in Europe's court," she said on Saturday. "We hope that it is possible to find a solution."
Tweeting that the parties could not stop at the "last mile", Mr Schulz confirmed earlier that he would meet Ms Freeland first, followed by talks with Paul Magnette, the premier of Wallonia.
What is Ceta?
Canada and the EU would eliminate 98% of tariffs under Ceta, which was negotiated over five years between 2009 and 2014.
Supporters say this would increase trade between them by 20%.
Critics argue that the deal lowers product standards and protects big business, allowing corporations to sue governments, even for profits they have yet to make.
Why does success hinge on one small region?
Wallonia is a region of just 3.6 million people. The EU as a whole has a population of 508 million while there are 36.3 million Canadians.
Belgium's constitution stipulates that each of its regional governments must back the deal before the federal government can sign it.
Wallonia has remained steadfast in opposing Ceta, seeing it as a threat to farmers and welfare standards.
The French-speaking region has a strong socialist tradition. Its fears echo those of anti-globalisation activists, who say Ceta and deals like it give too much power to multinationals - power even to intimidate governments.
There have also been big demonstrations in several EU countries against Ceta and the TTIP trade talks between the EU and the US.
How big a deal is this for Canada?
The deal was completed under the former Conservative government but is a major priority for the Liberals, who are under pressure to boost the country's economy, the BBC's Canada editor Jessica Murphy writes.
They dispatched special envoy Pierre Pettigrew, a former cabinet minister with a wealth of experience in international trade, to help save the flagging agreement.
Federal Trade Minister Chrystia Freeland has repeatedly met European leaders in recent months to shepherd it through.
On Friday, she said agreement now seemed "impossible".
How does the EU look now?
The failure to clinch the EU-Canada Ceta deal is an embarrassment, writes Laurence Peter, the BBC website's EU analyst.
The European Commission insists Ceta is not over but it also refuses to unpick the massive text.
Chances of any EU free trade deals with the US, China or India now look remote. Anti-globalisation groups, anxious to protect Europe's welfare and environmental standards, may feel they are winning the argument.
For now, any Ceta boost for small businesses and jobs has been postponed.
Are there lessons for Brexit?
A very obvious one is that it is going to be difficult for the EU to implement trade and investment deals, perhaps with anyone, writes Andrew Walker, the BBC's economics correspondent.