French business leaders have been pitched into fresh uncertainty by snap parliamentary elections called by President Emmanuel Macron, which risk strengthening the far-right.

Federations are treading lightly with their public comments, aware that they could be sitting across the table from National Rally (RN) ministers if the party scores a major breakthrough in the June 30 and July 7 ballots.

Local business group U2P would "respect the people's choice, but the RN has to say more precisely what it proposes on questions with a tax, social and economic effect on small firms," its chief, Michel Picon, told Agence France-Presse (AFP).

At the last presidential election in 2022, the group had warned that RN chief Marine Le Pen's campaign promises "would have bad consequences for business," he recalled.

At stake are issues such as returning to an official retirement age of 60 – raised to 64 in a wildly unpopular Macron reform last year – and a still harsher crackdown on immigration.

"What does this mean for people working for us today?" Picon asked.

"We're business players who don't get involved in politics," said Thierry Cotillard, head of the Mousquetaires/Intermarche supermarket chain.

But "whoever the politicians are, we will fiercely defend our positions," he warned.

Investors have clearly signaled their alarm with heavy selling of French stocks – the benchmark CAC 40 index of blue chips slumped 1.4% on Monday and 1.3% on Tuesday.

Yields on French government bonds have also spiked, suggesting growing doubts about France's capacity to finance its spending if the RN keeps its promises into practice.

Macron's Finance Minister Bruno Le Maire warned that, "If the RN carries out its program, a debt crisis in France is possible."

Earlier Tuesday, he had preached to business leaders to "stick their neck out" against the far-right.

Risk of 'distrust'

Centrist Macron's time in office has been marked by reforms aimed at making life easier for businesses and high-profile courting of foreign investment.

In contrast, "we know nothing" about the RN's plans, said the head of one major European industrial firm's French subsidiary, on condition of anonymity.

"We've just seen the beginnings of a reindustrialization for 10 years, with supply-side policies bearing fruit. Will all that be kept up?" he asked.

Without naming any party, the main employer's federation MEDEF told AFP that, "A new campaign is starting in which we do not share certain political visions, which are incompatible with business competitiveness and prosperity for our country and fellow citizens."

Such proposals "would inevitably lead to further deterioration of our public finances and tax cuts for households and companies," it added.

The CPME small-business group, for its part, called for supply-side policies, greenhouse emissions cuts and welfare state reforms to continue.

It also warned of France's staggering 3 trillion euro ($3.2 trillion) debt pile, which ratings agency Moody's said Monday risked a downgrade due to the "potential political instability" from the upcoming election.

"Anyone taking on costly reforms without taking this element into account would be exposing France to a major risk," the CPME said.

One sector with particular fears for a far-right victory is renewable energy, which has already been waiting for months on a government roadmap stretching to 2035.

"What's going on is serious," said Jules Nyssen, president of the Renewable Energies Union (SER).

"We're in a state of total instability, just when we need legal guarantees and clarity," he added. "It's going to cost us heavily.

"We have a clear road map that we need to eliminate carbon emissions," said Nicolas de Warren, president of the UNIDEN association of big industrial energy users.

"What's essential for us is access to low-carbon electricity at competitive prices, whether it's nuclear or renewable."

In 2022, Le Pen promised a fleet of around 20 new nuclear reactors – though her 2031 timetable for delivering half of those was seen as unrealistic.

But she is also a committed opponent of wind energy, vowing a moratorium on new construction and the gradual dismantling of existing parks – plans that are incompatible with France's climate commitments.

"The laws of economics and energy will catch up" with the RN if it comes to power, one electricity provider said on condition of anonymity.

"We need more cheap energy. Building nuclear takes 10-15 years. What do we do while we wait? And how do we attract battery factories if we don't want any more electric cars?" he added, citing another of Le Pen's bugbears.