French President Francois Hollande has warned against attempts to disrupt Euro 2016 with strike action, as the football tournament gets under way.
France has been in the grip of industrial action, mainly over reforms to labour law.
Train drivers are threatening to strike on a line serving the Stade de France in St Denis just outside Paris, where France play Romania in the first match.
Meanwhile, a brawl in Marseille led to two England fans being arrested.
Tear gas was fired and police in riot gear were on the streets after the incident outside a pub shortly before midnight on Thursday. England play Russia in the city on Saturday.
Mr Hollande said everyone had a duty to ensure that the competition was allowed to proceed without incident.
“I appeal to everyone’s sense of responsibility because if the state must do its duty – and it will, it will take all the measures that are necessary,” he said.
“At the same time, it is also necessary that those who are taking part in actions, or who are organising them should also shoulder their responsibility… so that this great event can be a shared popular festival.”
Transport Minister Alain Vidalies told Europe 1 radio that if the government had to “issue orders” for trains to be driven to get fans to the opening match, “we will do so”.
“If requisitioning is required… we will do it,” he said. “There will be no more negotiating.”
Sports Minister Thierry Braillard appealed to the unions to think about the football fans.
“While there are times when strikes can take place, we are now on the eve of an event during which they are going to prevent some fans from getting to the stadium,” he said.”That’s just not normal.”