Iran says President Donald Trump's claim the US shot down an Iranian drone is false, with one official joking that the US most likely destroyed one of its own by mistake.

On Thursday, Trump said the USS Boxer destroyed a fixed-wing unmanned aerial system that came within "threatening" range over the Strait of Hormuz.

Seyed Abbas Araghchi, Iran's deputy foreign minister, derided the claim on Friday, tweeting: "I am worried that USS Boxer has shot down their own UAS by mistake!"

The Pentagon rejected Iran's denial that the US took down one of its drones. A spokesperson told INSIDER, "We stand by our statement from yesterday."

The incident is the latest of several tense exchanges in the Persian Gulf, with US and UK forces involved in skirmishes since Iran said it was breaching limits on enriched uranium agreed under the 2015 nuclear deal.

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Iran laughed off President Donald Trump's assertion that the US shot down an Iranian drone on Thursday, with one official saying the country was "worried" the US actually destroyed one of its own.

"We have not lost any drone in the Strait of Hormuz nor anywhere else," Iran's deputy foreign minister, Seyed Abbas Araghchi, tweeted early Friday.

"I am worried that USS Boxer has shot down their own UAS by mistake!"

—Seyed Abbas Araghchi (@araghchi) July 19, 2019

On Thursday, Trump said the USS Boxer destroyed an Iranian drone that had come within "threatening" range of the amphibious assault ship as it sailed through the Strait of Hormuz.

A map showing the Strait of Hormuz, a narrow mouth of the Persian Gulf where 18.5 million barrels of oil pass through every day. Google Maps/Business Insider

"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," the chief Pentagon spokesman, Jonathan Hoffman, told Business Insider's Ellen Ioanes.

Read more: Iranian gunboats backed away in a showdown with a Royal Navy frigate after staring down the barrel of the 'perfect weapon'

"A fixed-wing unmanned aerial system approached Boxer and closed within a threatening range," he added. "The ship took defensive action against the UAS to ensure the safety of the ship and its crew."

The Pentagon did not immediately say how the drone was destroyed, but CNN cited a US defense official as saying the ship had used electronic jamming to down it.

Iranian President Hassan Rouhani and Trump. Michael Gruber/Getty Images; Olivier Douliery-Pool/Getty Images; Samantha Lee/Business Insider

On Friday morning, Iran's Revolutionary Guard said it would be releasing images to disprove Trump's claim, Reuters reported, citing state media.

"Soon, images captured by the Guards drones from the US warship Boxer will be published to expose to world public opinion as lies and groundless the claim ... of shooting down an Iranian drone over the Strait of Hormuz," it said.

Meanwhile, the Pentagon rejected Iran's denial that the US took down one of its drones.

Cmdr. Rebecca Rebarich, a Pentagon spokeswoman, told INSIDER, "We stand by our statement from yesterday."

Trump at the White House on Friday reiterated the administration's claim regarding the Iranian drone. "We shot it down," Trump said.

Wall Street Journal reporter Rory Jones, who was aboard the USS Boxer in the hours before it took down the drone, on Friday reported that he'd witnessed an Iranian helicopter as well as a military vessel come dangerously close to the Boxer.

Tensions in the Persian Gulf have intensified since Iran said it would breach its limit on low-enriched uranium, disregarding promises it made under the 2015 nuclear deal, known as the Joint Comprehensive Plan of Action.

Read more: The UK is deploying another warship to the Persian Gulf as concern grows over a tanker that went missing near Iran

The US pulled out of the deal in May 2018, and relations between the two states have become increasingly frosty since then. Tensions have heightened in recent weeks after a series of skirmishes at sea in the waters around Iran.

On June 13, Japanese and Norwegian oil tankers were attacked in the Gulf of Oman. Iran swiftly denied responsibility.

An oil tanker on fire in the Gulf of Oman on June 13. AP Photo/ISNA

A video released by the US military the next day purported to show Iran Revolutionary Guard boats taking an unexploded limpet mine from the hull of the Japanese tanker.

On June 20, Iran shot down a US Navy RQ-4 Global Hawk drone. Trump quickly called the clash "a mistake," avoiding an escalation.

Tensions between Tehran and the West heightened further, however, when the UK seized an Iranian ship entering the Mediterranean through the Strait of Gibraltar, claiming it was illegally transporting oil to Syria.

Iran then responded by ordering all "foreign powers" to leave the Strait of Hormuz, saying the West was playing a "dangerous game."

The US has sent thousands of additional troops and fighter jets to the region amid the mounting tensions.