It's the first day on the job for the new French prime minister, and the long-announced date for a Yellow Vests-style day of protest against austerity. Sébastien Lecornu is taking over from predecessor François Bayrou, who also passed on the bigger political hot potato – a budget that still needs passing. Bayrou was undone by an opposition-led parliament.  

The 39-year old Sébastien Lecornu is unknown to many, yet he's been in every government since Emmanuel Macron's second month in office back in 2017. Wednesday's Yellow Vests-inspired "Block everything" movement started on social media, adopted by the hard left, and is part of the pushback against further cuts to the welfare state in a nation still brooding over pension reform, the scrapping of the wealth tax and –more broadly – the disconnect between elites and the disenfranchised.

Read moreCan Macron’s quiet power broker Sébastien Lecornu navigate France’s fractured politics as PM?

Will naming a loyalist further stoke resentment against the term-limited Macron? Or can his quiet man succeed where previous heads of government have failed in striking deals with a hostile parliament? Lecornu may promise a new approach, but can Macron himself change, and resist the temptation to override eventual compromises?

Produced by Alessandro Xenos, Rachael Griffiths and Juliette Brown.