President Donald Trump on Saturday abruptly called off the “biggest attacks since World War II” against Iran in favor of negotiations, the latest in a seemingly endless series of whiplashes in the conflict.

The energy markets, which typically favor stability and predictability, responded with little more than a shrug.

Crude prices dipped slightly and gas prices remained steady. Even as the war stretches past the six-month mark and the midterms creep closer, Trump has been able to keep retail prices lower than experts say they should be through the sheer power of promises – which have yet to come through – of a swift end to the conflict. On Monday, he took that a step further, chastising the major oil companies for “making too much money” off global oil shortages as a result of the war.

“They better cut the retail price, the consumer price,” Trump said. “I’ll say it loud and clear. I’m not happy about it.”

But Trump’s ability to jawbone the markets may be diminishing at a critical time, three months before the midterm elections when control of Congress is hanging in the balance and his approval is sinking to new lows amid voter anger over cost of living concerns. It comes as global crude oil supplies are running low, the war threatens more energy flows, refiners are running out of spare capacity and the administration has few tools to keep gas prices low.

“Labor Day is the point where gas prices are baked into the election,” said Republican pollster Frank Luntz. “That last summer trip determines how voters evaluate their cost of living.”

And the higher gas prices come at a time when Trump repeatedly promises to escalate the war and then says it’s almost over a few hours or days later. That is starting to degrade his ability to cause price drops, a former adviser cautioned.

“His credibility has been a little bit shot,” said a former Trump adviser close to the White House, granted anonymity to avoid reprisal.

“The markets aren’t paying attention to him, they’re paying attention to what’s happening and, with respect to oil prices, it is a huge liability for the Republicans,” the adviser said.

Trump on Monday acknowledged that dynamic but expressed no urgency. He told reporters in the Oval Office that he was in no rush to end the conflict, though he acknowledged the need to fully reopen the Strait of Hormuz, through which about 20 percent of global energy supplies flowed before the war. He hinted at the midterm stakes for his party if the conflict does not end soon.

“I’m under no time constraint,” he said. “I don’t happen to be running, but a lot of very good Republicans are running.”

Trump’s ability to move the markets may be the only tool the administration has left to keep gas prices in check, said Rory Johnston, an oil market researcher and founder of the Commodity Context newsletter.

The Trump administration has drawn down the U.S. Petroleum Reserve to its lowest level since President Ronald Reagan’s first term. Oil majors are warning that the lack of refinery capacity could keep prices high for the foreseeable future.

“The market is so entrenched on this idea that eventually this will resolve by Trump deciding and ceding some ground on some issue, likely kind of even symbolic control of the Strait of Hormuz,” he said. “So the market’s going to be constantly watching for any sign that he’s shifting there.”

While experts continue to marvel at Trump’s ability to get the markets to bend to his whims, there is little consensus on when that power will dissipate.

Trump has “less credibility” in terms of moving markets, but it has not totally dissipated, Patrick de Haan, head of petroleum analysis at pricing service GasBuddy.

“I don’t think credibility completely goes to zero,” he said. “Hard to know though when it really bends.”

Trump’s push to keep energy prices low has also been buoyed by reduced Chinese oil imports, the successful rerouting of about 7 million barrels per day of Saudi Arabian crude through the Red Sea and releases from strategic petroleum reserves.

The administration released nearly 3 million barrels of oil from the Strategic Petroleum Reserve last week, bringing the reserves down to their lowest level since February 1983, according to Department of Energy data. About half of the 218.5 million barrels the Department of Energy said it would make available to the market have now left the salt caverns along the Gulf Coast.

As the summer driving season winds down, consumers expect gas prices to fall as well.

If the national average price of a gallon of gas is still above $4 by Saturday, de Haan noted, it will set a new record for the latest in the calendar year that prices are so high.

Ben Lefebvre contributed to this report.

President Donald Trump is stuck.

Iran has made clear that its price for ending hostilities is control over the Strait of Hormuz, a politically unpalatable prospect for the White House. But the ongoing tit-for-tat strikes, threatening to become a wider regional war, is equally untenable.

That’s left a frustrated White House with few good options, five former Trump administration officials told POLITICO.

“Iran wants the political concession of the principle that they get money for passage through the strait,” said a former administration official, granted anonymity to speak candidly. “That will embed their control of the strait in diplomatic practice and customary law.”

Trump over the previous weeks has mixed threats of destruction with promises of resolution, a pattern that continued this weekend. On Saturday night, Trump posted on Truth Social that he had called off an attack on Iran, “subject to being able to rapidly make a DEAL” to open the strait.

“We have just been asked by Iran, and other Middle Eastern Countries, to hold off any attack in that the perimeters of a deal has been agreed to,” he wrote. “This would include the Immediate, Complete, and Total OPENING OF THE HORMUZ STRAIT, and an end to Iran’s nuclear threat.”

The announcement followed media reports suggesting Trump was preparing new, intense strikes on Iran, possibly on the country’s energy infrastructure, which could certainly escalate the conflict. But Iran has not yet responded to Trump’s announcement and has not confirmed that a deal with Washington has been reached.

Nor is there any indication that Iran is willing to relinquish control of the strait.

Inside the White House, top administration officials, including Secretary of State Marco Rubio, have warned against any resolution that allows Iran to control the strait.

Doing so, they believe, would imperil the United States’ future ability to sanction Iran because multiple countries would need waivers to pay the fees. It would further reduce the international community’s ability to pressure Iran into giving up its nuclear ambitions. And Rubio last week warned it would create a dangerous precedent sure to be duplicated.