President Donald Trump said Thursday that a US Navy ship patrolling the Strait of Hormuz shot down an Iranian drone that came to within 1,000 yards (meters) of the vessel.

The drone was "threatening the safety" of the USS Boxer and its crew and was "immediately destroyed," Trump said at the White House during a joint press conference with Dutch Prime Minister Mark Rutte.

"This is the latest of many provocative and hostile actions by Iran against vessels operating in international waters," the president said.

"The United States reserves the right to defend our personnel, our facilities and interest and calls upon all nations to condemn Iran's attempts to disrupt freedom of navigation and global commerce," he said.

Shortly after Trump's remarks, the Pentagon issued a statement on the incident.

"At approximately 10 a.m. local time, the amphibious ship USS Boxer was in international waters conducting a planned inbound transit of the Strait of Hormuz. A fixed wing unmanned aerial system (UAS) approached Boxer and closed within a threatening range. The ship took defensive action against the UAS to ensure the safety of the ship and its crew," Pentagon spokesman Jonathan Hoffman said.

The Iranian foreign minister, Mohammad Javad Zarif, was visiting United Nations headquarters in New York on Thursday.

When asked by reporters about Trump's announcement, he said, "we have no information about losing a drone."

Tensions in the Persian Gulf have increased in the last few months amid attacks on oil tankers that Washington blamed on Iran and the June 19 shootdown of a US surveillance drone that Tehran says violated its airspace, though the Pentagon said the aircraft was flying over international waters.

Trump, despite steadily expanding the US military presence in the region, insists that he does not want war with Iran, pushing instead for a dialogue along the lines of the one he has pursued with North Korean leader Kim Jong-un.

Iranian leaders, however, reject the idea of any negotiations until and unless Trump brings the US back into the multilateral 2015 pact under which Tehran accepted limits on its nuclear power program in return for relief from economic sanctions.

Washington pulled out of the accord in May 2018 and has imposed increasingly severe sanctions with the proclaimed intent of crushing the Iranian economy.

Iran recently breached a central pillar of the nuclear deal by producing more than its 300-kg limit of enriched uranium.

While the Trump sanctions have focused on the Islamic Republic's banking and oil sectors, they have also effectively prevented Iran from exporting its excess enriched uranium.

The US move to block uranium exports left Tehran with a choice of either ending enrichment entirely or exceeding the stockpile limit. EFE