Paris: Protesters blocked roads with burning tyres in a northern French port Thursday as workers and students staged a fresh strike to demand the withdrawal of a hotly contested labour bill.

Demonstrations as well as work stoppages, notably in the aviation and public transport sectors, are planned across France.

Hundreds of strikers, mainly dockworkers, set up flaming roadblocks at all the main access routes around the port of Le Havre, the all-news BFMTV channel reported.

Civil aviation authorities said passengers at Paris’s Orly could expect one in five flight cancellations.

Opponents to the reform, billed as an effort to lower France’s stubborn 10 percent unemployment, say it is too pro-business and will threaten cherished workers’ rights and deepen job insecurity for young people.

They plan to pile on the pressure with further protests on Sunday, the traditional 1 May labour day, as well as next Tuesday, when parliament begins debate on the bill.

A wave of protests against the reform began on 9 March, culminating in a massive outpouring of anger on 31 March when sometimes violent demos brought 390,000 people to the streets, according to an official count, while organisers put the number at 1.2 million.

That spawned a new movement dubbed ‘Up All Night’ that has seen advocates of a broad spectrum of causes occupy city squares overnight for the past four weeks, though attendance has been dwindling.

Show business workers who have occupied Paris’s Odeon since Monday planned to repeat the action across France on Thursday — although an accord was reached late Wednesday for the terms of their unemployment insurance.

France’s deeply unpopular President Francois Hollande has been banking on the labour reform as a standout initiative with little more than a year left in his term.

But in the face of the protests his Socialist government watered down the labour reforms — only to anger bosses while failing to assuage workers.