Prime Minister Justin Trudeau issued a blunt warning to European lawmakers today: sign off on a free trade deal with Canada or risk reducing the European Union's relevance.

Trudeau formally welcomed French Prime Minister Manuel Valls for a three-day visit to Canada, holding a news conference after a private meeting on Parliament Hill.

"If, in a week or two, we see that Europe is unable to sign a progressive trade agreement with a country like Canada, well then with whom will Europe do business in the years to come?" Trudeau asked in French. "In this post-Brexit situation where there are a great many questions about Europe's usefulness, if Europe cannot manage to sign this agreement, then that sends a very clear message not just to Europe, but to the whole world, that Europe is choosing a path that is not productive for its citizens or the world. And that would be a shame."

Valls said France is a champion for the Comprehensive and Economic Trade Agreement (CETA) because it will be a strong jobs generator and boost for both economies. He called it "unfathomable" that Europe would not agree to the accord.

"If the EU does not participate in a positive, win-win agreement with Canada, then with whom will the EU be able to build such free trade agreements?" he asked.

CETA blocked in Belgium?

Trudeau was planning to travel to Brussels to officially sign the agreement later this month, but some countries have been slow to agree to its ratification.

Austria's chancellor, for example, only began to show tentative signs of support last week after a major lobbying effort led by Canada's allies in the German social democratic party.

This week, key regional government votes in Belgium's southern region of Wallonia appear poised to thwart plans to have the EU's trade ministers sign off on the deal next Tuesday.

Valls was asked about efforts to bring Belgium's regional dissenters onside.

"We are doing everything we can to convince our Walloon friends that this agreement is a good thing for Canada and the European Union," he said. "France is fully committed to this agreement."

I was honoured to welcome French PM <a href="https://twitter.com/manuelvalls">@manuelvalls</a> today as we strengthen the partnership & friendship between Canada and France. <a href="https://t.co/7b1P6PKoUb">pic.twitter.com/7b1P6PKoUb</a> —@JustinTrudeau

The French are working in tandem with Canadian International Trade Minister Chrystia Freeland and her parliamentary secretary, David Lametti, who both have travelled to Belgium to try to sell the deal.

Lametti — specifically tasked with bringing the Belgians around — hosted a delegation from Wallonia in Canada this month.

Valls also was asked about French Green MEP José Bové's speaking tour in Canada this week. The outspoken anti-free trade activist is working to stop the deal from being ratified in Brussels.

Bové was detained for several hours at Montreal's airport Tuesday and missed a speaking engagement.

"I have a great deal of sympathy for José Bové, but he does not represent all of France or all of the European Parliament," Valls said.

Canada a 'key partner'

Valls praised Canada as a key partner in fighting the biggest challenges confronting the world, from the "scourge" of terrorism to fighting climate change. The French PM also praised Trudeau for reassuming a leading role on the global stage.

Valls arrived in Ottawa on Wednesday evening and had a private, working dinner with Trudeau and their officials before Thursday's official events.

Governor General David Johnston met French Prime Minister Manuel Valls at Rideau Hall Wednesday evening. (Fred Chartrand/Canadian Press)

When Valls arrived on Parliament Hill Thursday morning, the pair took part in an official welcoming ceremony that included a 19-gun salute, followed by a wreath laying in the Memorial Chamber of the Peace Tower.

On Thursday afternoon, the two leaders moved on to Montreal, where they joined Quebec Premier Philippe Couillard for a business luncheon hosted by the Montreal Chamber of Commerce to promote CETA.

Valls is in Canada until Friday.

French Prime Minister Manuel Valls, Quebec Premier Philippe Couillard and Prime Minister Justin Trudeau met business leaders in Montreal ahead of a luncheon event to promote the Canada-EU free trade agreement. (Paul Chiasson/Canadian Press)

'No advice' on peacekeeping

The two leaders also discussed Canada's plans for sending peacekeepers to West Africa to join the fight against Islamic militants.

The Trudeau government has said it will commit 600 peacekeepers to UN missions, and France has been pushing Canada hard to join the UN mission in West Africa.

La France et le Canada, c'est une relation très forte, une longue amitié forgée par l'Histoire. Merci au PM <a href="https://twitter.com/JustinTrudeau">@JustinTrudeau</a> pour son accueil. <a href="https://t.co/LJxeFHbPau">pic.twitter.com/LJxeFHbPau</a> —@manuelvalls

Trudeau confirmed discussions included operations in Africa, but said Canada is still figuring out the best ways to help in the world. Defence Minister Harjit Sajjan is meeting with top peacekeeping officials at the United Nations in New York Thursday.

Valls said France will offer "no advice" to Canada on important decisions, but stressed the importance of offering support and training to African armies in countries like Mali.

"We are glad that Canada is back. It is important for us, and I know it will translate into concrete actions," he said.

France has 3,000 troops fighting a separate counter-insurgency mission in several countries that used to be its colonies, under the banner of Operation Barkhane.