Police are expecting around 30,000 people to attend, with one source saying they feared problems from hard-left troublemakers. "The organiser has been warned of these fears," said the official.
The march was called back in July by Jean-Luc Mélenchon, leader of the hard-left La France Insoumise.
He has made the protest something of a pet project over the past few weeks and called on unions and colleagues in the Nouvelle Union populaire écologique et sociale (Nupes) alliance to back his plans.
However on Wednesday, LFI MP Alexis Corbière was asked for a projected ballpark figure of expected protesters. He sidestepped the question, admitting concern that the final figures would be ‘a disappointment’.
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An unnamed LFI official told Le Parisien: "It's complicated to put a million people in the street (...) We have no idea what we can mobilise in the Paris region.”
The long-planned march comes amid growing social tension over the government's use of strike-breaking powers, and plans to reform the pension system. A one-day strike is called for Tuesday, October 18th.
Four days before the planned protest, Nupes activists relaunched their call to march on social networks with the hashtag #Tufaisquoile16.
They have also chartered dozens of buses to bring as many people as possible to Paris for the march from Place de la Nation to the Bastille. Bus tickets cost between €5 and €50, based on income.
There is some support for the day of protest against pension and unemployment reforms, the Macron government’s expected budget plans, and climate change issues. Organisers have the backing of some 700 trade unionists and associations, 600 student organisations and a number of well-known French faces - including new Nobel literature laureate Annie Ernaux. But confirmed figures are currently well down on great expectations.
The march begins at 2pm in the Place de la Nation and heads along a 2km route before finishing in the Place de la Bastille. Some roads along the route will close and Metro stations in the area may also close while the march is underway, although lines will continue to run.
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