Youth organisations and unions are demonstrating on the same day as a rail strike over a wage dispute.

The proposed law would remove some of the protection workers enjoy against being laid off, in a bid to encourage businesses to hire more people.

But many on the left see it as a betrayal of their values.

In pushing the reform, Prime Minister Manuel Valls has united a formidable array of leftist forces against him, says the BBC`s Hugh Schofield.

That includes not just the unions but much of his own Socialist party - plus the students, who are leading Wednesday`s protests.

The rail strike has already created disruption in Paris, with only one in three trains running and long queues of traffic, said reports.

Sit-ins and street marches are planned later in the day across the country - though heavy rain in the capital and elsewhere threatened to deter some protesters.

Is this shaping up to be the great trial-by-street that every French government seems to end up facing? That is the question on this first day of protests against Manuel Valls`s new labour law.

The reform has certainly crystallised all those forces on the left who, while feeling increasingly unhappy about the government`s drift, until now had no clear-cut issue around which to rally.

Wednesday is an important test because if students turn out en masse, it will be ominous for the government. Everyone has in mind the student protests of 2006, when a similar proposal to loosen labour protection had to be withdrawn by the then centre-right government.

The proposed law has the Valls-Macron tandem written all over it. They represent the liberalising, pro-business wing of the Socialists. Right now they have the president`s ear - but if the country turns massively against their reform, who knows what may happen?

President Francois Hollande`s four years in office have been marked by poor economic growth and spiralling unemployment - now reaching 10% and 24% among youth.

The government of Mr Hollande, who faces presidential elections next year, is aiming to address those issues - with reforms to France`s labour code, which is famously longer than the bible.

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