Oil prices edged higher after U.S. President Donald Trump doubled down on his threats to attack Iran’s civil infrastructure, warning that the nation will be “taken out in one night,” if the Islamic Republic’s leadership failed to reopen the Strait of Hormuz.

U.S. West Texas Intermediate crude futures for May were up 0.93% at $113.46 per barrel as of 8:45 p.m. ET. Brent crude for June delivery gained about 0.54% to $110.36 per barrel.

On Monday, Trump repeated his threat that the U.S. will destroy Iran’s power plants and bridges if Tehran did not reopen the Strait of Hormuz by 8 p.m. ET on Tuesday, while also signaling that Iranian leadership was negotiating in earnest.

The closure of the narrow waterway connecting the Persian Gulf and Gulf of Oman has led to a supply shock, sending prices for crude, jet fuel, diesel, and gasoline soaring since the war broke out on Feb. 28.

“They have ’til tomorrow,” the president said. “Now we’ll see what happens. I can tell you, they are negotiating, we think in good faith, we’re going to find out. We’re getting the help of some incredible countries that want this to be ended, because it affects them also.”