France is bracing for massive disruption to transport and public services ahead of "Black Thursday", its first major strike triggered by the global financial crisis.
All the country's main trade unions have called for their members to stay away from work to take part in large-scale street protests against President Nicolas Sarkozy's right-wing government.
With businesses failing and unemployment mounting, many workers fear they will be made to pay the price for a crisis they blame on the greed of bankers and a failure in market capitalism.
Sarkozy, who came to power 20 months ago promising to cut taxes and trim France's public administration, has announced a €26 billion ($34 billion) industrial stimulus package.
But he has also set aside €360 billion to underwrite banks and has signaled he intends to press ahead with most planned reforms to shake up the public sector and liberalise the labour market.
Opposition Socialists, who have been flailing in the political wilderness since Sarkozy's May 2007 election victory, have seized upon the protest movement to thrust themselves back into the debate.
"We're the opposition. Did you think we were just going to lie back and wait for 2012?" declared Socialist leader Martine Aubry, referring to the date of the next presidential vote.
Thursday's protests will see mainstream Socialist politicians once more marching alongside organised labour and the hard left. "All the unions are telling us, 'It's good to have you back'," Aubry said.
Both the government and the unions are expecting the strike - which opinion polls have indicated are thus far supported by a majority of the public - to cause widespread disruption.
Airlines will have to cancel a third of flights departing and arriving at Paris's Orly airport and 10 per cent of those from the main Charles de Gaulle hub, aviation officials said.
The SNCF state rail company said only 60 per cent of TGV high-speed trains would run and warned of even greater disruption on regional trains.
Only 35 per cent to 50 per cent of Lyria high-speed services will connect to Switzerland, but Eurostar trains to London and Thalys trains to the Netherlands and northern Germany will not be affected, it said.
Metro and Parisian commuter train services will be badly disrupted, the RATP transport authority said, but the city's buses and trams are planning to run normally, albeit crowded with overflow Metro passengers.
"Workers, the unemployed, the vulnerable, pensioners, everyone who is suffering must not hesitate to take part. To be heard, we need to mobilise in great numbers," said Bernard Thibault, head of Communist union the CGT.
Sarkozy's government has been careful in its approach to the protests, striking a conciliatory tone and postponing reforms to secondary education which could have provoked teenagers to join the marchers.
But some of the president's right-wing allies have spoken out.
Laurence Parisot, the head of the French employers' federation MEDEF, attacked the strike movement as the wrong answer to the crisis.
"We all agree on the diagnosis, we are going through a crisis of unequalled proportions," she told France Inter radio, confirming that transport shutdowns would keep many non-striking private sector staff from their posts.
"But ... it is bad news that France's only response should be this kind of hodge-podge, blanket protest. It is as if a sailor caught up in a storm started shouting at the weather, instead of holding the tiller."