Updated 2:02 a.m. July 20.
VOA National Security Correspondent Jeff Seldin contributed to this report.
WHITE HOUSE — Iran is "nothing but trouble," U.S. President Donald Trump said after the Islamic Revolutionary Guard Corps seized two British-owned oil tankers Friday in the Strait of Hormuz.
"We heard it was one, we heard it was two. We'll be working with the U.K.," Trump said on the White House South Lawn in response to a question from VOA. "We have no written agreement [with the British]. But I think we have an agreement that is long-standing."
Iran's maritime authorities had requested the capture of the British-flagged Stena Impero for "not following international maritime regulations," according to the guard corps, which is a branch of the Iranian armed forces.
Saturady Iran's Fars news agency reported that the Stena Impero was in an accident with a fishing boat and ignored its distress call before being detained. All 23 crew members are at Bandar Abbas port and will stay there until the investigation is finished, according to Fars.
The owners of the Stena Impero, which was heading to Saudi Arabia, said they had been unable to contact their vessel, which had 23 personnel on board. It was "heading north towards Iran" after being approached by "unidentified small crafts and a helicopter" in the strait, the owners said.
Officials in London said Iranian forces also briefly detained a second British-owned Liberian-flagged oil tanker, the Mesdar, on Friday. The Mesdar's owner confirmed the vessel had been released, and tracking data showed the tanker was heading west into the Persian Gulf.
British government officials called the detention of the two tankers unacceptable and a violation of the free passage of vessels in international waters.
"These seizures are unacceptable,'' said Jeremy Hunt, Britain's secretary of state for foreign and commonwealth affairs. He said London would "respond in a considered but robust way" to Iran's action, but that "we are not looking at military options, we are looking at a diplomatic way to resolve the situation."
A U.S. military spokesman, Lt. Col. Earl Brown with Central Command, said Friday that unarmed surveillance aircraft were monitoring the Strait of Hormuz from international airspace, and that the U.S. military had contacted U.S. ships to ensure their safety.
In another development, state media in Saudi Arabia reported that the government had given approval to allow several hundred U.S. forces in the country to boost regional security. U.S. officials told The Associated Press that the move was meant to counter Iran, but said the action had been planned for weeks and was not a response to Friday's seizure of the tankers.
Friday's actions by Tehran appeared to be retaliation for the detention of a supertanker in the British Mediterranean territory of Gibraltar.
Authorities there on Friday extended for 30 days the holding of a Panamanian-flagged supertanker, the Grace 1. It was seized this month by British Royal Marines on suspicion of violating sanctions against Syria by attempting to transport Iranian crude oil to Syria.
Drone shot down
Earlier in the day, Trump expressed confidence an Iranian drone had been downed Thursday in the strait as it approached a U.S. warship.
"No doubt about it. No. We shot it down," Trump told reporters in the Oval Office.
"There's no question that this was an Iranian drone," Trump's national security adviser, John Bolton, chimed in. "The USS Boxer took it out as the president announced yesterday because it posed a threat to the ship and its crew. It was entirely the right thing to do."
Asked before news of the seizure of the oil tankers became public if he was worried about a broader clash with Iran in the strait, Trump replied he was not.
"We hope for their sake they don't do anything foolish,” he said. “If they do, they will pay a price like nobody's ever paid a price."
VOA later asked Trump if seizing the tankers was foolish, but he declined to answer specifically.
Bid to break 'status quo'
Speaking Friday at a security forum in Aspen, Colorado, U.S. Defense Intelligence Director Lt. Gen. Robert Ashley said Iran was at what he described as an inflection point because of economic strife caused by U.S. sanctions.
"What you see is an attempt to break that status quo," Ashley said.
"We saw this coming a couple of weeks out," he told the audience, adding that while Tehran does not want war, "there's always the possibility of miscalculation."
Earlier Friday, a senior administration official told reporters the Defense Department was expected to release video evidence of the drone shootdown.
Iran denied the U.S. military had shot down one of its drones.
"We have not lost any drone in the Strait of Hormuz nor anywhere else," Iran's Deputy Foreign Minister Abbas Araghchi posted on Twitter, adding he was "worried" that the U.S. amphibious assault ship had shot down an American military drone "by mistake."
"The Iranians don't have a great history with the truth," responded a senior U.S. official to the assertion from Tehran. "They have a 40-year history of provoking us."