The Yemeni group says it will continue targeting Israel-linked commercial vessels until aid reaches Palestinians in Gaza.

The sanctions, announced on Thursday, target four key Houthi officials over their roles supporting or directing attacks on commercial shipping in the Red Sea, the US and UK said.

“The Houthis’ persistent terrorist attacks on merchant vessels and their civilian crews … threaten to disrupt international supply chains and the freedom of navigation, which is critical to global security, stability, and prosperity,” Brian Nelson, the US Treasury’s undersecretary for terrorism and financial intelligence, said in a statement.

“Today’s joint action with the United Kingdom demonstrates our collective action to leverage all authorities to stop these attacks.”

Those sanctioned were Houthi Defence Minister Mohamed Nasser al-Atifi; commander of Houthi naval forces Muhammad Fadl Abd al-Nabi; coastal defence forces chief Muhammad Ali al-Qadiri; and Muhammed Ahmad al-Talibi, who the two governments described as the Houthi forces’ director of procurement.

The UK said the four men were involved in acts which “threaten the peace, security and stability of Yemen”.

British Foreign Secretary David Cameron said in a statement that the restrictions “reinforce our clear message to the Houthis in recent weeks”, promising to target those behind the “unacceptable and illegal actions” against shipping.

War on Gaza

The sanctions have come as Houthi leader Abdel-Malek al-Houthi promised to continue the attacks that have disrupted international commerce in the Red Sea and the Gulf of Aden.

“Our country will continue its operations until food and medicine reach the people of Gaza,” al-Houthi said in a televised speech on Thursday.

Since November, the Houthis have carried out dozens of attacks on commercial vessels they have said were linked to Israel. They said the operations were meant to pressure Israel into stopping its war on Gaza.

The group’s leader added that US and British military action in Yemen conducted in response to the Houthi attacks would not affect their “will and determination”.

On Monday, a new round of attacks targeted a Houthi underground storage site as well as missile and surveillance capabilities used by the Iran-aligned group against Red Sea shipping.

The Houthi attacks have disrupted international commerce along a route that accounts for about 15 percent of the world’s shipping traffic. Several shipping companies have redirected their vessels around the southern tip of Africa, delaying delivery times and adding a further 3,000-3,500 nautical miles (6,000km) to their route.

The US also re-designated the Houthis as “Specially Designated Global Terrorists” (SDGTs) earlier this month, a designation attributed to those who are considered to “threaten the security of the US”.

In response to the designation and the US and British attacks against targets in Yemen, hundreds of thousands of people have taken to the streets of Yemen’s capital Sanaa and other cities to protest and to show support for Palestinians in Gaza.