Travelers beware: French labor unions plan a string of strikes in the coming days that will target trains, the Paris subway system, ports and possibly airports.

Unions are tapping months of public anger over a labor bill that would make it easier for employers to fire workers and lengthen the working week.

They're hoping the timing of the walkouts, which start with train service Tuesday, will increase pressure on the government to withdraw the bill: They're happening just as France prepares to host the month-long Euro 2016 European soccer championship, which begins June 10 and is expected to draw 2.5 million people to stadiums around the country.

Signs emerged in recent days that both sides might be ready for compromise, after Prime Minister Manuel Valls spoke with the head of the CGT union, whose hard-left flank is leading the protest movement.

The degree of strike-related chaos will depend on how many workers take part. Unions have staged several strikes this year, but typically only a minority of staff participates, and a 2007 law requires a minimum level of service on all transport during strikes.

Workers at the SNCF rail authority — whose service will be crucial to Euro 2016 spectators — go on strike starting Tuesday night. The Paris transit authority, RATP, starts striking Thursday. Air traffic controllers are threatening to join in starting Friday.

Fuel shortages are another concern. Striking workers have blocked or slowed production at most of France's eight refineries, and disrupted oil imports at ports around Marseille on the Mediterranean and Le Havre on the English Channel.

Blockades at fuel depots last week caused nationwide gasoline shortages, but the situation has eased somewhat since the government ordered police to clear out protesting workers. Picketers had been blocking an oil depot in Port-de-Bouc near Marseille but police ended that protest Monday.

Unions in each sector are negotiating for different demands specific to their workers, unrelated to the overall labor bill. But the bill has become a rallying cry. The government argues France needs the reform to survive in the global economy but critics say it strips away hard-fought worker protections and won't create the jobs it promises.