Taxis, air traffic, civil servants, teachers ... what are the French striking about now?

Twenty striking taxi drivers were arrested on Tuesday and another injured, as France was hit by work stoppages and protests that also involved air traffic controllers, civil servants, teachers and farmers. A fifth of flights were cancelled and roads blockaded by cabbies and farmers.

A striking French taxi driver holds a flare during a demonstration in Marseille Reuters/Jean-Paul Pelissier

Prime Minister Manuel Valls condemned "inadmissible" violence on taxi-drivers' picket lines at airports and on the roads after meeting representatives of unions and employers, both of whom backed the stoppage.

But he announced a consultation procedure and said he would appoint a mediator to help reslove the dispute.

About 1,500 taxis were reported to be mobilised to protest at Paris's Charles De Gaulle and Orly airports, preventing access at the latter for a while, and on the Paris ringroad, which was blocked in the morning.

There were also protests in regional cities, notably Marseille, Toulouse and Lille.

Air traffic authorities said that a fifth of flights were cancelled, as it requested, but no late cancellations were needed.

Air France said that all its long-haul flights had taken off as had 80 per cent of flights within France and Europe.

Women hold a banner reading "That's enough!" as they take part in a demonstration, on 26 January, 2016 in Lyon. Jean-Philippe Ksiazek/AFP

Thousands of civil servants and teachers demonstrated across the country, notably in Marseille, in the south, and Rouen, north of Paris.

Farmers have been blockading roads in Brittany for several days and have been joined by others in the central Massif Central mountains this week.

So what were the disputes about?

• Taxi drivers and companies claim they have lost 20-30 per cent of their trade, partly because of tourist numbers falling after November's Paris attacks but mainly because of "unfair" competition from operators like Uber, whose drivers do not to have to buy the expensive licences that professionals need and, they claim, are dodging rules brought in by the govenrment, such as a ban on picking up passengers in the street.

• Air traffic controllers say that government austerity policies mean they are understaffed, leading to stress and worsening security;

• Civil servants are angry at a pay freeze in place since 2010, which unions claim means a loss of 8-10 per cent in spending power over the last five years;

• Teachers are also affected by the salary freeze but are also striking against a controversial reform of middle schools, which includes mixing subjects in the same lessons, more autonomy for schools and reduction of teaching of Latin and ancient Greek;

• Farmers claim that prices paid by retailers for milk, beef and pork are now so low that they are losing money and that outbreaks of bird flu in the south-west and bluetongue, which effects sheep, have hit sales.

The government on Tuesday announced 290 million euros in aid to farmers, 130 million euros of which were to go to poultry breeders in the south-west, one of whose chief money-spinners, foie gras, has been hit by a partial ban on exports.