Up to a thousand tractors will block roads in Paris on Wednesday as French farmers protest against government policies and international trade agreements which they say are hurting their businesses and living standards.

Farmers unions said members heading to the capital from across France would converge on Avenue Foch, near the Champs Elysees and Arc de Triomphe, later on Wednesday.

‘The government is leaving us exposed, let us work,’ one farmer wrote on his tractor.

The demonstration is being staged by the two main farm unions, which called for a meeting with President Emmanuel Macron to express concerns about government policies they say harm French agriculture.

‘We want to warn everyone that if there are no more farmers in France it has a knock on effect on the French economy,’ 29-year-old farmer Alix Heurtaut told Reuters in an interview earlier this week.

Resentment among farmers has been growing at what they call ‘agri-bashing’, or criticism of agriculture over issues ranging from pesticide use to animal welfare.

Attacks on livestock farms and butcher's shops by vegan activists have caused particular outrage. Longstanding tensions with environmental associations have meanwhile deepened amid debates about banning the common weedkiller glyphosate and restricting pesticide use near residential areas.

Some farmers blame Macron for rushing to ban glyphosate by 2021, going beyond current European Union policy, although the government has promised exemptions for farms that have no viable alternative.

Macron has also been under pressure from farmers over EU trade deals with Canada and the Mercosur bloc of South American countries, which farming groups say will usher in imports of cheaper agricultural goods produced to lower standards.

A food law passed by Macron's government, which aimed to give farmers a fairer share of profits, has also failed to dispel discontent over modest revenues.

Farm unions are gearing up for negotiations over the next EU budget, which could see agricultural spending trimmed due to Britain's planned exit from the bloc.

France is the largest agricultural producer in the EU and the biggest beneficiary of subsidies under the EU's Common Agricultural Policy.