Yemen's Iran-backed Houthi rebels threatened on Saturday to attack any vessels heading to Israeli ports unless food and medicine were allowed into the besieged and war-hit Gaza Strip.
The latest warning comes amid heightened tensions in the Red Sea and surrounding waters following a series of maritime attacks by Houthi rebels since the start of the Israel's brutal military campaign in Gaza on October 7, which has killed over 17,700 Palestinians.
In a statement posted on social media, the Houthis said they "will prevent the passage of ships heading to the Zionist entity" if humanitarian aid is not allowed into the enclave.
The Houthis have recently attacked ships they claim have direct links to Israel, but their latest threat expands the scope of their targets.
Regardless of which flag ships sail under or the nationality of their owners or operators, Israel-bound vessels "will become a legitimate target for our armed forces", the statement said.
Israel's national security adviser, Tzachi Hanegbi, said his country would not accept the "naval siege", noting Prime Minister Benjamin Netanyahu had asked US President Joe Biden and European leaders to take measures to address the situation.
"If the world will not take care of it," Hanegbi warned on Israel's Channel 12 television, "we will take action to remove the naval siege."
Last week, the Houthis attacked two ships off the Yemeni coast, including a Bahamas-flagged vessel, claiming they were Israeli-owned.
And last month, the rebel forces seized the Galaxy Leader, an Israeli-linked cargo vessel.
"We warn all ships and companies against dealing with Israeli ports," the latest Houthi statement said.
It added that all "ships linked to Israel or that will transport goods to Israeli ports" are not welcome in the Red Sea, a vital channel for global trade linked to the Suez Canal.
Beyond maritime attacks, the Houthis have launched a series of drone and missile strikes targeting Israel in response to Tel Aviv's indiscriminate bombing and siege of the Gaza Strip, ongoing since October 7.
Israel has targeted key infrastructure, such as homes, schools, refugee camps and hospitals, and has placed the enclave under a complete siege, cutting off water, food and fuel supplies to 2.3 million Palestinians.
The spike in maritime incidents prompted G7 foreign ministers at a meeting earlier this month to urge the rebels to cease threats to international shipping and to release the Galaxy Leader.