That policy now threatens to leave the world with a shortage of crude oil and rob Americans of the gasoline price relief they usually get in the autumn. It may even leave drivers paying more at filling stations in the fall, just as they are preparing to cast their votes in elections that could hand Democrats control of the House, cnbc.com reported.
President Donald Trump appeared to get his way just over a week ago when two dozen oil producers agreed to pump more crude to tame rising crude prices. Worried that Trump's sanctions on Iranian oil exports would cause Americans pain at the gas pump, his administration reportedly lobbied Saudi Arabia for the hike.
But just days after OPEC announced its decision, the State Department sent oil prices soaring by announcing a policy that threatens to wipe out much of Iran's oil exports in the coming months. By Saturday, Trump was tweeting that he'd asked Saudi Arabia's king to raise output by up to two million barrels per day (bpd) — double what the Saudis and their allies agreed to the previous week.
The White House later walked back Trump's claim on Twitter that King Salman bin Abdulaziz agreed to his request, and analysts are uncertain the Saudis can deliver. Making matters more difficult, the Trump administration has imposed a deadline on oil buyers to cut off purchases from Iran by November 4 — just two days before most Americans vote.
To be sure, it remains unclear to what extent higher gasoline prices would hurt Republicans at the polls, or whether voters will connect Trump's policies to gas costs. However, the threat of elevated fuel prices comes as the US trade war with its biggest trade partners risks putting upward pressure on consumer prices and denting Americans' view of the economy.
Trump's Iran policy 'risky'
The president himself has repeatedly cast blame for surging oil prices on OPEC. The group has limited its output for the last 18 months to shrink a global glut of oil that sent crude prices to 12-year lows, bankrupted hundreds of US energy companies and piled pressure on petrostates.
That strategy put oil prices on a steady road to recovery, but analysts say it is clear that Trump's hawkish stance on Iran, the world's fifth largest oil producer, is largely responsible for the recent rally.
The recovery accelerated ahead of Trump's decision in May to abandon the 2015 Iran nuclear deal and restore sanctions on the country. The cost of crude surged more than 14 percent over the last three months, with international benchmark Brent crude racking up its biggest quarterly gain in nearly six years and US crude posting its best quarter in two years.
Last week alone, US crude surged more than eight percent, closing above $74 per barrel for the first time since November 2014. Analysts say the main catalyst was the State Department's announcement on Tuesday that the administration is telling oil buyers to stop importing Iranian crude by November 4. That shocked the market, which anticipated Trump might allow buyers to gradually reduce their purchases, a model created by the Obama administration.
Trump's much more aggressive strategy means US crude could soon rise to $80 per barrel, said Helima Croft, global head of commodity strategy at RBC Capital Markets.
"If we're going to go through with this strategy, if we are clearly intent on taking a million and half, two million Iranian barrels off the market, that's what we have to reconcile ourselves to," she told CNBC's 'Power Lunch' on Friday.
That strategy is 'very risky' because it leaves the oil market with few options in the event of supply disruptions, according to Croft. Venezuela's production is already on pace to fall by as much as one million bpd this year, she said, while surprise outages in Libya and Canada significantly reduced supplies last week.
"We can't afford any more supply disruptions if we're going to be that aggressive in taking Iranian barrels off the market," she said.
OPEC, Russia and several other producers are aiming to increase output by about one million bpd. However, analysts are skeptical they'll meet that target and say the market can easily sop up the extra supply. At the same time, US crude oil output is rising, but labor shortages and pipeline bottlenecks in the nation's biggest oilfield are capping growth.
Trump may cause pain at the pump
Given those obstacles, crude oil prices could rise enough to offset the seasonal decline in gasoline prices that Americans usually enjoy in the autumn, said Andrew Lipow, president in Lipow Oil Associates.
If Brent crude rises another $10 to $90 a barrel, the cost of a gallon of regular gasoline would top today's national average of $2.85, according to Lipow. The same goes for jet fuel and the diesel that powers the nation's shipping fleet.
"As a result, the consumer should expect to pay more for their airline tickets," he said. "Higher diesel prices are going to be passed through to the consumer in higher prices for goods and services."
Patrick DeHaan, senior petroleum analyst at GasBuddy, expects Americans to see a smaller-than-usual dip in gas prices this fall, due to bullish oil market factors like Trump's tough stance on Iran.
"The national average usually will decline anywhere from 20 to 35 cents. This year it might only be 5 to 10, maybe 15 cents, if we're lucky," he said.
The US government's Energy Information Administration recently forecast that the national average gasoline price is unlikely to breach $3 per gallon, after topping out at $2.96 at the end of May. But some analysts are not convinced.
"I would take the bet with the EIA that maybe we haven't seen the highest prices of the year because there's just too much going on and too many things that can lift gasoline," said Tom Kloza, global head of energy analysis at Oil Price Information Service.
Those include potential outages at refineries that process crude into fuels, or hurricane season storms that knock out part of the nation's oil drilling, refining and transportation system. Refiners are also focused on making jet fuel and diesel right now because those products have better profit margins than gasoline, according to Kloza.
It is also uncertain that the Saudis could meet Trump's request. While Saudi Arabia can certainly increase output, pumping an additional 2 million bpd would be "the biggest public test of Saudi's spare capacity", Croft told CNBC on Saturday.
Also on Saturday, the White House clarified that King Salman did not agree to hike output by 2 million bpd, as Trump suggested in his tweet. Instead, the king said Saudi Arabia would tap its spare capacity if and when it becomes necessary, and only after it consults with fellow oil-producing nations.
OPEC's next official meeting is not until December 3, though the group is expected to review market conditions in September at a special gathering announced last month. The Saudis would face the challenge of persuading OPEC members like Iran and Venezuela, which opposed an output hike last month.