Crude oil prices rose Thursday to reach their high levels since September after the Trump Administration warned Iran may face military strikes if the country does not negotiate a new nuclear agreement.

The price of Brent crude oil (BZ=F) jumped as much as 4.3% to briefly cross $70 per barrel for the first time since September before paring gains. The US pricing benchmark, West Texas Intermediate (CL=F) crude, gained as much as 4.7% to trade above $65 at its highs of the day.

The gains add to a run-up over the past month that has seen oil rise roughly 15% as geopolitical risk premiums and record cold weather in the US have buoyed prices.

“Oil markets are rapidly repricing geopolitical risk as the probability of direct US action against Iran rises,” said Rystad Energy head of geopolitical analysis Jorge Léon.

“The speed of the oil price reaction suggests markets see US military action against Iran as a real, near-term risk.”

The US military has positioned naval vessels and other equipment capable of striking inside the country over the past week as President Trump has ratcheted up threats of action against the Iranian regime over a new nuclear weapons deal with the US.

“A massive Armada is heading to Iran. It is moving quickly, with great power, enthusiasm, and purpose … Like with Venezuela, it is, ready, willing, and able to rapidly fulfill its mission, with speed and violence, if necessary,” the president wrote in a Truth Social post on Wednesday.

“Hopefully Iran will quickly ‘Come to the Table’ and negotiate a fair and equitable — NO NUCLEAR WEAPONS — one that is good for all parties. Time is running out, it is truly of the essence!”

If Iran won’t negotiate, the president said, “The next attack will be far worse!” — a reference to the US’s strikes last summer on Iran’s Fordow Uranium Enrichment Plant.

The tensions between Washington and Tehran have kept worries alive around potential disruptions to the Strait of Hormuz.

The strait sees roughly 20 million barrels of crude oil and other petroleum products cross its waters every day, according to the Energy Information Administration, and disruptions would have wide ripple effects on supply and pricing.

On top of the geopolitical risk, the US crude market also saw an unexpected tightening last week.

Commercial crude inventories in the US for the week ended Jan. 23 decreased by 2.3 million barrels from the previous week, according to data released Wednesday by the Energy Information Administration. Analysts at Macquarie had expected a growth of 900,000 barrels.

A small boat loaded with merchandise sails past the St Kitt's and Nevis-flagged container ship Marsa Victory in the waters of the Strait of Hormuz off the coast of Khasab in Oman's northern Musandam peninsula on June 25, 2025.  (Photo by Giuseppe CACACE / AFP) (Photo by GIUSEPPE CACACE/AFP via Getty Images)

A small boat loaded with merchandise sails past the St Kitt’s and Nevis-flagged container ship Marsa Victory in the waters of the Strait of Hormuz off the coast of Khasab in Oman’s northern Musandam peninsula on June 25, 2025. (Photo by Giuseppe CACACE / AFP) (Photo by GIUSEPPE CACACE/AFP via Getty Images) · GIUSEPPE CACACE via Getty Images

Still, analysts say it is unlikely Iran would be able to fully close off the strait, even if the regime sought to do so.

“They’ve played that card so many times that it doesn’t really have any share,” Clay Seigle, a senior fellow at the Center for Strategic and International Studies, told Yahoo Finance.

But the strait is not Iran’s only lever. The Iranian regime has been under immense pressure as mass protests against the country’s religious governing regime have swept across the country, seeking to topple the Ayatollah.

Thousands of protesters have been killed by Iranian forces, raising fears of US intervention and potential disruption to oil markets if protesters were to attack key oil-exporting infrastructure along the Persian Gulf — and of potential retaliatory action from the regime.

“There have been instances in the past where Iran’s government has sent a reminder of its ability to cause disruption and chaos,” said Ben Cahill, director for energy markets and policy at UT Austin’s Center for Energy and Environmental Systems Analysis, referencing Iran’s “sabotage and attacks on tankers” in 2019 and attacks against oil infrastructure in the surrounding region.

“If the Iranian regime decides to lash out and cause havoc, there are multiple ways that it could do it,” Cahill told Yahoo Finance.

Jake Conley is a breaking news reporter covering US equities for Yahoo Finance. Follow him on X at @byjakeconley or email him at jake.conley@yahooinc.com.

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