Yemen's Houthis said on Tuesday they would resume attacks on Israeli ships passing through the Red and Arabian seas, the Bab al-Mandab Strait and the Gulf of Aden, ending a period of relative calm starting in January with the Gaza ceasefire.
The Houthis had launched more than 100 attacks targeting shipping from November 2023, saying they were in solidarity with Palestinians over Israel's war with Hamas in Gaza.
During that period, the group sank two vessels, seized another and killed at least four seafarers in an offensive that disrupted global shipping, forcing firms to re-route to longer and more expensive journeys around southern Africa.
The leader of Yemen's Houthis had warned on Friday that the group would resume its naval operations against Israel if it did not lift a blockage of aid into Gaza within four days.
On March 2, Israel blocked the entry of aid trucks into Gaza as a standoff over the truce escalated, with Hamas calling on Egyptian and Qatari mediators to intervene.
"This ban will remain in effect until the crossings to the Gaza Strip are reopened and humanitarian aid, including food and medical supplies, is allowed to enter," the group said in an emailed statement on Wednesday, adding that the ban would take place with immediate effect.
The US State Department said earlier this month it was implementing the designation of the movement as a "foreign terrorist organisation" after US President Donald Trump's call for the move.
In January, Trump re-designated the Houthi movement as a foreign terrorist organisation, aiming to impose harsher economic penalties in response to its attacks on commercial shipping in the Red Sea and against US warships defending the critical maritime area.

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