OTTAWA—Prime Minister Justin Trudeau will finally travel to Brussels on Saturday to sign the Canada-EU free trade deal known as the Comprehensive Economic and Trade Agreement, or CETA.

The Prime Minister’s Office, which confirmed Trudeau’s off-again, on-again travel plans, says the postponed summit will now take place Sunday.

Trudeau had initially expected to sign the deal in Brussels earlier this week, but the restive Belgian region of Wallonia put the brakes on that plan by standing in lone opposition to the controversial deal.

In recent weeks, the tiny French-speaking region of 3.5 million people opposed the deal’s investor-state dispute settlement mechanism, with the support of other European politicians and anti-trade activists.

An agreement Thursday give national and regional parliaments throughout Europe new powers over those controversial investor protection provisions, prompting warnings from some observers that the pact remains a fragile one.

A final obstacle was removed Friday when Wallonia officially voted to withdraw their opposition to the deal.

Wallonia held a veto over Belgium’s ability to support the deal, which requires the support of all 28 EU countries. But its parliament voted overwhelmingly to allow the Belgian national government to support the pact.

The Council of the European Union adopted a package of decisions on matters such as signing the agreement, its provisional application and requiring the European Parliament’s consent to conclude the deal.

They also agreed to a joint text with Canada that provides a “binding interpretation” of the terms of the pact on certain issues, according to a statement on the council’s website.

“I am delighted to confirm that the EU is ready to sign the Comprehensive Economic and Trade Agreement with Canada, said Slovakian Prime Minister Robert Fico, the current president of the council.

“The CETA represents a modern and progressive deal, opening the door to new opportunities, while protecting important interests. Moreover, it has the potential to set the way forward for future trade deals.”

The Walloons dropped their opposition following an agreement Thursday with the Belgian government that gave national and regional parliaments throughout Europe new powers over controversial investor protection provisions.

That deal prompted warnings from some observers that the pact remains a fragile one.

Green party Leader Elizabeth May, long an opponent of the Canada-EU deal, urged Trudeau to stay home and host a debate on the agreement “so that Canadians understand the stakes of CETA, including its use of risky foreign investor provisions.”

“This agreement undermines environmental regulations and will favour multinational companies at the expense of Canadian sovereignty,” May said in a statement. “In the current form, we must continue to oppose the adoption of CETA.”

Politicians in Wallonia had argued that the proposed deal would undermine labour, environment and consumer standards and allow multinationals to crush local companies. Supporters said it would yield billions in added trade through customs and tariff cut.