French President Emmanuel Macron Saturday faces what could be the largest protests and disruptions in his 18 months in office.

Opposition parties have egged on a grassroots movement threatening to block traffic across the country over higher gasoline prices. The government has said it won’t bar any protests, but it won’t allow any roads to be blocked. More importantly, it’s not backing down on higher gasoline taxes, which it sees as part of its long term goal of weaning France of fossil fuel.

“It’s a political protest with the Republicans behind it, and it’s irrational because the rising taxes have been compensated by the decline in the oil market,” Interior Minister Christophe Castaner said on BFM television Nov. 13. “We hear the protests, we hear the anger, I know the situation, but we have to explain that it’s essential that we exit fossil fuels.”

A petition on Change.org calling for lower gasoline taxes has more than 852,000 signatures. A website [url=http://www.blocage17november.com]http://www.blocage17november.com[/url] lists planned protests in all of France’s 95 mainland departments. Agence France-Presse says 700 blockages are planned. The movement, which has branded itself “gilets jaunes”—after the yellow safety vests drivers need to keep in their cars—blames higher taxes on fossil fuels for rising prices at the pump.

Opposition Opportunity

While the movement calling for the protests isn’t linked to any political party, all opposition groups have tried to associate with it.

“This government hasn’t understood the anger of the French,” Socialist Party secretary general Olivier Faure said in a statement Wednesday. The president “hasn’t listened to the French people,” the leader of the Republicans, Laurent Wauquiez, said in a tweet Nov. 1, adding that he’ll take part in the protests. “We were the first party to express our total support for this movement,” said nationalist leader Marine Le Pen in an interview Nov. 13 with Le Parisien.

Macron, asked about the movement during an interview on France’s aircraft carrier Wednesday evening, said he “hears the anger” but said he was “wary because many different people are trying to piggyback on this movement.” In earlier interviews, he has said he prefers taxing fuel to taxing labor.

Polls Approval

Diesel prices at the pump in France have risen 16 percent this year to an average 1.48 euros ($1.67) a liter, though the price did hit 1.53 euros in early October, according UFIP, the French oil industry federation. Gasoline is up 5 percent to 1.47 euros per liter, after peaking at 1.57 euros.

Taxes account for about 60 percent of the price at the pump in France. The government increased its hydrocarbon tax at the start of the year by 7.6 cents per liter on diesel and 3.9 cents to gasoline, and a new boost at the start of next year will add another 6.5 cents per liter of diesel and 2.9 cents per liter of gasoline, part of an effort to bring diesel and gasoline taxes in line.

An Elabe poll released Nov. 14 said 73 percent of the French approve of the protests and 70 percent think the government should roll back recent gas tax increases. Several videos by angry drivers have gone viral on social media.

No Backing Down

Macron has so far been spared the kind of protests his predecessors have faced. Street demonstrations against the labor market liberalization pushed through by Macron shortly after his May 2017 elections never gathered critical size to worry the government. Further, rail strikes last Spring, though causing some disruptions, fizzled out as the government pressed ahead with a reform of the state train system, which eventually passed parliament.

Prime Minister Edouard Philippe Nov. 14 reiterated the government wouldn’t back down on the higher taxes, but doubled the public incentives to buy cleaner cars or boilers to up to 4,000 euros a car. This failed to alleviate the “yellow vests’” concerns.

France is trying to end its addiction to diesel, fueled by decades of government support. Diesel once represented three-quarters of cars sold in France, but the ratio has declined to just below 40 percent as it progressively lost its tax advantage.

Contrary to its reputation for public transport, about 70 percent of the French drive to work everyday, according to state statistical unit Insee, compared with about 76 percent in the U.S.