Paris, France - More than 400,000 protesters mobilised across France for a fourth round of protests, as talks between unions and the government fail to break the stalemate over plans to overhaul the pension system.

Thursday also saw transport strikes, the longest France has witnessed for decades, enter a 36th day.

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Teachers, lawyers, nurses, and pilots joined transport workers at Place de la Republique in eastern Paris, where they called on the government to abandon proposed changes to the national pension system and demanded better working conditions.

"France cannot lose its social model," Isabelle Tranquet, a flight attendant for Air France, told Al Jazeera. "I'm thinking about my son ... he cannot lose these social protections."

Under the proposed changes, 42 special retirement programmes would be consolidated into a universal, points-based system.

While the official retirement age would remain at 62, workers would be incentivised to work until 64 in order to receive their full pension. The system would be implemented gradually, starting with those born after 1975.

Self-employed workers also joined the mix over fears of having their pension contributions doubled by the reform.

"With the new reform I'll go from contributing 14 percent to 28 percent of my salary," Dominique Bergougnoux, a self-employed speech therapist told Al Jazeera. "It's like the government thinks we're invisible, but that's why I've come out today, to say that I'm here."

Laurence Derrey, a 55-year-old teacher, told Al Jazeera she feared the reform would force her colleagues to work longer for a lower pension.

"We cannot accept this, everyone has a right to earn a decent living," Derrey said. "If we let this reform go through, we'll be sending people into poverty."

Laurent Berger, the head of France's moderate CFDT union, told reporters on Wednesday that they were "still far from an agreement," on the reform.

Meanwhile, his counterpart, Philippe Martinez, of the hardline CGT Union, signalled he had given up on talks with the government, telling French radio station Europe 1: "We can see that the door is closed."

CGT called for a four-day blockade of fuel refineries, prompting fears of petrol shortages. Along with other unions, it has also called for a fifth round of demonstrations on January 11.

An Odoxa-Dentsu poll released on Wednesday showed that 61 percent of French people were against making people wait until the "pivotal age" - 64 - in order to receive a full pension. They wanted that part of the reform to be scrapped.

At the same time, support for the demonstrations has dwindled.

A recent Ifop poll by the French paper Le Journal du Dimanche found that only 44 percent support the strike, a 6 point drop from the start of the movement on December 5.

The poll also found that 75 percent believed French President Emmanuel Macron would not back down.

Businesses reported major losses during the holiday season as a result of the strikes.

In Paris, retail sales were down between 30 and 50 percent in December, typically one of the most profitable periods for retailers because of the holiday season.

In his New Year's Eve address, Macron said he would push through with the reform.

Scrapping it, he said, would be "a betrayal to our children and their children after them, who would have to pay the price for our giving up."

A new round of talks is scheduled for Friday.