Jordanian air defences have shot down 18 of 20 ballistic missiles fired by Iran towards an American military base in Jordan, according to an official spokesperson for the Jordanian Armed Forces.

The remaining two missiles fell in unpopulated areas, Jordanian authorities confirmed, in Tehran's direct response to US strikes on five Iranian oil tankers.

US Central Command (Centcom) confirmed earlier that American forces targeted the tankers after Iran attacked a US warship twice over the past two days. Centcom said the warship successfully evaded the missiles and no US personnel were harmed.

Four of the targeted tankers were operating in the Gulf of Oman with links to Iran's Revolutionary Guards Corps (IRGC), while a fifth was struck near Kharg Island. The terminal off Iran's Gulf coast handles approximately 90% of the country's crude oil exports piped from the mainland.

Washington said the vessels formed part of a multi-billion-dollar shadow network funding the IRGC and its regional proxies.

Iran has issued further warnings to commercial maritime traffic, urging crews aboard US-linked tankers near ports in Kuwait and Bahrain to leave their vessels immediately as they will be targeted.

Speaking to reporters during a visit to Colombia, US Secretary of State Marco Rubio said the position was straightforward, warning that Iran would lose tankers every time it attempted to hit US naval ships.

The escalating exchange comes more than six months after the US and Israel launched joint attacks on Iran on 28 February, further destabilising energy markets already under strain.

On Tuesday, Yemen's Iran-backed Houthi movement struck energy facilities and civilian infrastructure in Saudi Arabia, injuring 73 people and forcing temporary operational shutdowns, according to Saudi military and energy authorities.

Earlier on Tuesday, Iran's navy claimed to have seized an uncrewed American submarine in the Strait of Hormuz. US Navy Captain Tim Hawkins, speaking for Centcom, clarified that the vessel was an older-model underwater survey drone that had malfunctioned and carried no classified radar, sonar, or sensitive data.

I will continue monitoring whether Iran follows through on its threats to commercial shipping around Bahrain and Kuwait, and how regional defences respond if missile exchanges widen further.