“We are going to keep the Strait. We will probably run it,” Trump told Fox & Friends Monday during a phone interview. “We’ll become the guardian of ⁠the Strait. Maybe we’ll call it the ‘guardian angel’ of the Strait.”

He added that the U.S. would ideally then be “reimbursed” for their guardianship of the waterway by “other” nations.

Soon after, Trump announced that the U.S. is reinstating its naval blockade against Iran and will charge 20% on all cargo shipped through the Strait to cover “any and all costs necessary to do the job of providing safety and security to this very volatile section of the world.”

Trump’s remarks came as oil prices soared by more than 3% Monday morning after the U.S. and Iran traded further strikes over the weekend.

Brent crude, the international benchmark, neared $80 per barrel, a significant rise from the same time last week, when it traded at $71.99.

Although prices remain well below the $126 peak reached in April, during the height of the war, the surge reflects the concerns over shipments transiting the Strait, which has a threat level of “severe” due to high volatility in the area.

Stocks in Europe and Asia also fell at the start of the week, and Wall Street futures dipped amid the geopolitical tensions.

U.S. and Iran trade strikes amid tussle over Strait of Hormuz

The U.S. military on ​Saturday evening said it had begun “launching the third round of strikes this week against Iran” after Iranian forces “blatantly attacked” a Cyprus-flagged container ship transiting the Strait.

Late Sunday afternoon, U.S. forces launched additional strikes against Iran “to continue degrading their ability to attack civilian mariners and commercial ships freely transiting the Strait” after Tehran said it had disabled a second vessel, this time off the coast of Oman.

Iran retaliated by again targeting U.S. assets in Bahrain, Kuwait, Jordan, and Oman.

The hostilities continued into Monday morning, with Bahrain—home to the U.S. Navy’s Fifth Fleet—reporting it had intercepted multiple Iranian missiles. Jordan also said it had intercepted missiles that entered its airspace from Iranian territories.

Esmail Baghaei, the Iranian Foreign Ministry spokesman, argued that Iran had not been the first to violate the peace agreement and insisted the country had “entered negotiations with meticulousness and seriousness.”

Tehran, over the weekend, reported it had closed the Strait of Hormuz, with Iran’s IRGC later stating the only way to fully reopen the waterway was to “end the interventions of the aggressive U.S. military.”

Trump has insisted the Strait is open, yet commercial traffic remains well below normal levels.

Ship-tracking data from Kpler, cited by Reuters, showed that only six vessels transited the Strait on Sunday. This is far lower than the 138 vessels that typically passed through the waterway each day prior to the war.

Since U.S. and Iranian officials signed the Memorandum of Understanding on June 17, there has been an attempt to reduce Iran’s chokehold over the Strait by routing commercial vessels along a southern corridor hugging Oman’s coastline. But Iran has repeatedly warned vessels against using any alternative routes.

Meanwhile, the U.S.-Iran cease-fire appears to be in tatters after Trump last week told NATO summit attendees that the interim agreement was “over.”

The MoU laid out the terms for an extended 60-day cease-fire, allowing time for further technical talks to take place.

That deadline is set to expire in mid-August, but amid flare-ups of violence and accusations of violations from both sides, it seems little progress has been made in negotiations.