Spain's parliament on Thursday approved the ratification of the Comprehensive Economic and Trade Agreement, a free-trade deal between Canada and the European Union that is set to eliminate about 98 percent of the tariffs between the two parties.

The lower chamber's plenary session ratified the agreement with 179 votes in favor, 79 against and 81 abstentions, the latter of which came from the Spanish Socialist Workers' Party (PSOE).

The Socialists said they abstained as a "warning" in light of the "new European framework" in which it was necessary to review some international treaties with the aim of achieving a fairer global trade.

PSOE leader Pedro Sánchez, who was recently re-elected as the party's secretary-general after being forced to resign back in Oct., had campaigned in the primaries on a position in favor of trade, but with certain conditions: any deals needed to uphold public services and guarantee social and labor rights, as well as consumer and environmental protections.

The ruling conservative Popular Party, the business-friendly Ciudadanos ("Citizens") and the center-right regional Basque Nationalist Party and Democratic Party of Catalonia all voted in favor of ratification, thus surpassing the 176-vote threshold needed for a simple majority and ensuring the bill's passage.

Spain's deputy prime minister, Soraya Sáenz de Santamaría, criticized the PSOE's abstention and said it was an anti-European position that was counter to progress.

Ciudadanos leader Albert Rivera also slammed the Socialists' neutral stance and condemned those who opposed CETA, whom he accused of aligning with French far-right politician Marine Le Pen's rejection of free trade.

"If there's a country in the world with which Europe can sign a treaty, it's Canada," Rivera added.

Both the PP and Ciudadanos said in their defense of the agreement that it would create new opportunities for Spanish small and medium-sized enterprises and claimed it would have a positive impact of 12 billion euros ($13.7 billion) in the EU and 8 billion in Canada.

Meanwhile, Pablo Bustinduy, the foreign affairs spokesman for the left-wing coalition Unidos Podemos _ which voted against ratification _ said CETA did not take the public interest into account and described the treaty's approval process as "defective" and "full of vices."

"They want to impose their model of a society without its citizens," Bustinduy said, adding that the PP was legislating "against the people's sovereignty."

CETA was officially signed on Oct. 30, 2016, although it has not yet entered into force since only three of the EU's 28 current members have ratified it: Latvia (Feb. 23), Denmark (June 1), and now Spain.

While the deal is fairly popular in Canada _ where a Feb. poll showed 55 percent of Canadians supported it and only 10 percent opposed it _ there have been numerous protests against CETA in several European countries.

CETA's critics allege that it favors big corporations while hurting consumer rights, that it will boost unemployment and that it will have a negative environmental impact.

One of the most heavily-lambasted aspects of the deal is the provision for an investor-state dispute settlement mechanism, which many detractors say would infringe on national sovereignty.