Ten months after he stormed from nowhere to seize the French presidency, Emmanuel Macron faces his sternest test yet as he seeks to cut the once hallowed privileges of rail workers and other public sector employees.

Undeterred by an 11 per cent slide in his approval ratings, Mr Macron is braving the fury of militant unions that have forced previous presidents into humiliating U-turns.

Emboldened by his successful labour reforms last year, Mr Macron is calculating that public opinion will shift in his favour. Polls show that 70 per cent of the public already back his rail reforms amid widespread dissatisfaction with train services. Many French people now accept that the country can no longer afford to spend more than 56 per cent of its GDP on the public sector.

The battle with the rail unions marks a decisive moment, comparable to Margaret Thatcher’s confrontation with British miners in the 1980s. The unions have vowed to paralyse the country with strikes unless Mr Macron abandons his plans to end jobs for life and the right of the 260,000 workers of the debt-ridden, state-owned SNCF rail company to retire in their 50s.

Other public sector unions are also threatening strikes as Mr Macron axes preferential pension arrangements to bring them into line with the private sector.