Protesters are gathering in Paris as the French parliament prepares to vote on contested labour reforms.

Marches have been organised by seven unions and student organisations in the country's major cities.

The Eiffel Tower has closed for the day due to a strike by some of the employees. The company running the monument said there are not enough workers to open it while ensuring public safety.

Air France has warned customers of some delays and last-minute cancellations due to a strike by some air traffic controllers.

In Paris, unionists and workers will march under close police watch from the Place de la Bastille to Place d'Italie in the east of the capital. The police have been checking protesters' bags before letting them enter the area.

The Bill outlining the reforms has led to several protests across France in recent months, often involving violence. Five days ago, police allowed only a small march in Paris, to ensure security.

During two weeks of debate, the Senate, led by a conservative majority, has substantially changed the Bill to make it more pro-business.

Yet the labour reforms must be debated again in July at France's lower house of parliament, the National Assembly, led by a Socialist majority.

The Socialist government wants the reforms to make it easier to lay off employees, allow temporary extension of the working week and give company deals priority over industry-wide agreements. Some unions argue it would weaken workers' rights.

The head of the left-wing CGT union, Philippe Martinez, told reporters "public opinion is still largely against this text", before the Paris march began.