WASHINGTON — A U.S. warship on Thursday destroyed an Iranian drone in the Strait of Hormuz after it threatened the ship, President Donald Trump said. The incident marked a new escalation of tensions between the countries less than one month after Iran downed an American drone and Trump came close to retaliating with a military strike.

In remarks at the White House, Trump blamed Iran for a “provocative and hostile” action and said the U.S. responded in self-defense.

He said the Navy’s USS Boxer, an amphibious assault ship, took defensive action after the Iranian aircraft closed to within 1,000 yards of the ship and ignored multiple calls to stand down.

“The United States reserves the right to defend our personnel, facilities and interests and calls upon all nations to condemn Iran’s attempts to disrupt freedom of navigation and global commerce,” Trump said.

The Pentagon said the incident happened at 10 a.m. local time Thursday in international waters while the Boxer was transiting the waterway to enter the Persian Gulf.

“A fixed-wing unmanned aerial system approached Boxer and closed within a threatening range,” chief Pentagon spokesman Jonathan Hoffman said in a written statement. “The ship took defensive action against the UAS to ensure the safety of the ship and its crew.”

It was the latest in a string of moves by the U.S. and Iran that have brought them closer to armed conflict since early May when Washington accused Tehran of threatening U.S. forces and interests in Iraq and in the Gulf. In response, the U.S. accelerated the deployment of an aircraft carrier strike group to the Arabian Sea and deployed four B-52 long-range bombers to the Gulf state of Qatar. It also has deployed additional Patriot air defense missile batteries in the Gulf region since then.

Shortly after Iran shot down a U.S. Navy drone aircraft on June 20, Trump ordered a retaliatory military strike but called it off at the last moment, saying the risk of casualties was disproportionate to the downing by Iran, which did not cost any U.S. lives.

Iran claimed the U.S. drone violated its airspace; the Pentagon denied this.

Iran’s foreign minister, Mohammad Javad Zarif, said Thursday that Iran and the U.S. were only “a few minutes away from a war” after Iran downed the American drone. He spoke to U.S.-based media on the sidelines of a visit to the United Nations.

Earlier Thursday, Iran said its Revolutionary Guard seized a foreign oil tanker and its crew of 12 for smuggling fuel out of the country, and hours later released video showing the vessel to be a United Arab Emirates-based ship that had vanished in Iranian waters over the weekend.

The announcement cleared up the fate of the missing ship but raised a host of other questions and heightened worries about the free flow of traffic in the Strait of Hormuz, one of the world’s most critical petroleum shipping routes. One-fifth of global crude exports passes through the strait.

Associated Press writer Ian Phillips in New York contributed to this report.