With a key ratification vote expected late this year, Prime Minister Justin Trudeau told reporters at the World Economic Forum in Davos, Switzerland, Friday that he's meeting with the head of the European Parliament tomorrow to discuss the Canada-EU trade agreement.

"I've had many conversations with European leaders on the importance of signing and ratifying CETA [the Comprehensive Economic Trade Agreement]," Trudeau said in response to a question from CBC News.

"This is an important opportunity both for Canada and Europe and I'm looking forward to getting it signed," the prime minister said.

German Martin Schulz was elected president of the European Parliament in 2014. His support for a successful ratification vote could be critical in Trudeau's attempt to close a deal negotiated by his Conservative predecessor.

Prior to assuming the presidency — similar to a speaker in North American legislatures — Schulz was the leader of the Progressive Alliance of Socialists and Democrats (S&D) in Brussels.

This group of 190 members of the European Parliament (MEPs) is significant because unlike some parties in Brussels, it includes representatives from all 28 member states. S&D, currently the second-largest party in the legislature, is also considered a potential swing vote come ratification time.

In Schulz's home country, German social democrats have expressed skepticism about the EU's coveted trade deals with both Canada and the U.S.

While Chancellor Angela Merkel is supportive of CETA, public opinion is not firmly onside. Last October, over 250,000 protesters turned out to one anti-trade protest in Berlin.

Lobbying key, proponents say

CETA proponents have warned for months that Canada needed to do more lobbying in Europe.

The Conservative government led by Stephen Harper concluded negotiations with the European Union in August 2014. But it hasn't been signed by individual member countries yet, pending a legal scrub (vet) and translation into the EU's 23 languages. That process is still underway.

Meanwhile, dissent among European civil society groups skeptical of the trade deal, in combination with anxiety about its investment provisions, now threatens to draw enough political support among EU politicians in Brussels that CETA may fail.

A ratification vote is expected this fall, assuming member countries actually sign the deal this summer.

The agreement's investor-to-state dispute settlement (ISDS) provision would allow foreign corporations to sue a country whose arbitrary political decisions interfered with its business.

At first, the provision in Canada's proposed agreement drew little attention. But when the same provision became a feature in trade talks underway with the U.S., public opinion shifted.

Now both North American deals have drawn protesters to the streets and bled support among members of the European Parliament.

An estimated 250,000 demonstrators hit the streets in front of the Reichstag building in Berlin last Oct. 10 to demonstrate against proposed free trade agreements with Canada and the United States. (Gregor Fischer/dpa via The Associated Press)

'More than tinkering'

Last November, Sorin Moisa, a Romanian S&D MEP who sits on the EU's trade committee and is his party's "rapporteur" for CETA, wrote that Canada and the EU Commission still need to convince "a significant majority" of social democrats who oppose the current investment clause on principle.

"That is not an easy task and it will require more than tinkering with the controversial investor-state dispute settlement (ISDS) system," he wrote. "Should this upgrade not take place there is a very serious risk that the treaty would be rejected by the European Parliament."

"The number of MEPs opposing ISDS is much higher than the number of MEPs opposing CETA," he continued.

"ISDS is the thorn in the flesh of CETA. This reflects a high degree of social mobilisation in a few large member states of the European Union," Moisa said. "The only way to solve the problem is to confront it head-on."

CBC News reported Thursday that EU officials saw an opening in Canada's change in government, and went back to Canadian negotiators looking for a rework of the ISDS provisions in CETA.

A proposal now on the table would create a new court system for arbitrating trade disputes under CETA — something the EU characterizes as not re-opening negotiations, but simply refining the legal text under the guise of the ongoing scrubbing process.

The EU took the same proposal to the table with the Americans, but it's been met with a cool reception.

Freeland met trade commissioner

ISDS mechanisms are part of all Canadian trade agreements, including Chapter 11 in the North American Free Trade Agreement (NAFTA) and the proposed Trans-Pacific Partnership of 12 Pacific Rim countries.

The meeting with Schulz, Trudeau's last before heading home from Switzerland on Saturday, will be held in the afternoon at the Zurich airport.

Trudeau told reporters International Trade Minister Chrystia Freeland is "working very, very hard on this file and connecting with negotiators and parliamentarians."

"I'll continue to support her," he said.

Elsewhere at Davos on Friday, Freeland tweeted that she'd met with Cecilia Malmström, the Swedish politician currently serving as the EU's trade commissioner.

Great mtg w/ <a href="https://twitter.com/MalmstromEU">@MalmstromEU</a> of <a href="https://twitter.com/EU_Commission">@EU_Commission</a> to highlight importance and value of <a href="https://twitter.com/hashtag/CETA?src=hash">#CETA</a> <a href="https://twitter.com/hashtag/WEF16?src=hash">#WEF16</a> – Min Freeland <a href="https://t.co/1k3rSuzj0X">pic.twitter.com/1k3rSuzj0X</a> —@CanadaTrade

Last week, Freeland said that in addition to her talks with Malmström, Trudeau had been speaking with Merkel and French President François Hollande in an effort to shore up support for the deal.