Yemen's Houthi rebels vowed on Saturday to resume attacks on US ships if American forces join Israel's war on Iran.

"In the event that the Americans are involved in the attack and aggression against Iran alongside the Israeli enemy, the armed forces will target their ships and warships in the Red Sea," the Houthis said in a statement.

Last week, Yemeni security sources told The National that the rebels are considering resuming strikes on US targets in the Middle East and intensifying attacks on Israel in support of Iran.

US President Donald Trump said last month the Iran-backed Houthis “capitulated” and that America would stop strikes on the rebels after they agreed to cease attacking ships in the Red Sea.

The Houthis are part of the so-called Axis of Resistance, an Iran-led network that includes Hamas in Palestine, Hezbollah in Lebanon and armed groups in Iraq, whose aim is to deter Israel from conducting military action and countering its influence in the region. Many of the groups have fought against Iran's enemies in their respective countries.

The groups launched attacks on Israel as part of a support campaign for Hamas and the Palestinian people after the Gaza war broke out on October 7, 2023. But months of fighting with Israel, which holds clear military dominance, have eroded the operational capacity of the axis considerably.

Hezbollah was once considered Iran's first line of defence against Israeli attacks, but strikes against the group last year killed its political and military leaders and largely destroyed its arsenal. Lebanese officials have urged Hezbollah not to respond to Israeli attacks on Iran.

In Iraq, sources close to the government told The National this week that some of the most prominent militant groups have made it known that any US military intervention would trigger a response.