Marine Le Pen's far-right party stumbled, French President Emmanuel Macron's centrists crashed and incumbent conservatives surged ahead in the first round of regional elections.

What was meant to be a vote centred on local concerns like transportation, schools and infrastructure turned into a dress rehearsal for next year's presidential vote, as would-be presidential hopefuls seized on the regional campaign to test ideas and win followers.

Mr Macron's rivals on left and right notably denounced his government's handling of the pandemic.

The wrangling appeared to turn off some voters, and less than 34% showed up, according to polling agencies.

Ms Le Pen called the low turnout "a civic disaster that deformed the electoral reality of the country, and produces a misleading vision of the current political forces".

The result is a clear setback for Ms Le Pen's National Rally, though it came in second place in most regions, according to early official results and polling agency projections. It is hoping to win control of a region for the first time to boost her decade-long effort to legitimise a party long seen as an anti-democratic, anti-Semitic pariah.

It had been riding high in pre-election polls and had steered campaign discourse toward its favoured subjects of policing and immigration - though both are issues handled by the central government and not regional councils. The party dominated the first round of the last regional elections in 2015, but collapsed in the run-off as parties and voters banded together against it.

The result is also a deep embarrassment for Mr Macron, whose young Republic on the Move party had hoped to establish a regional foothold for the first time but failed to excite voters.

Projections from three polling agencies show the conservative Republicans party, which currently runs seven of mainland France's 13 regions, won the most overall votes on Sunday, at between 27-29%.

They were followed by the National Rally at 18-19%, then the Socialist Party and its allies, the Greens party, Mr Macron's Republic on the Move and far-left France Unbowed. Early official results from each region reflected a similar breakdown.

Parties that win more than 10% of the vote advance to the run-off, which will determine the number of seats each party gets on regional councils.

Many polling stations stood largely empty as voting kicked off in schools and community centres from Marseille on the Mediterranean coast to Le Touquet on the English Channel. Those who did show up to vote had to stay masked and socially distanced and carry their own pens to sign voting registries.

Mr Macron's party did not exist the last time voters chose regional leaders in 2015. It is facing disillusionment with Mr Macron's policies, including from rural voters who supported the yellow vest uprising against perceived economic injustice.

The virus played only a minor role in the voting. As infections have ebbed and vaccinations spread, the French government recently reopened restaurants, shops and travel possibilities. Beginning on Sunday, the prime minister scrapped an unpopular overnight coronavirus curfew, just in time for the election.