WASHINGTON: Operatives from Iran and its Lebanese ally Hezbollah are working inside Yemen to support Houthi insurgents鈥� attacks on international shipping, a US official said Tuesday.

Tim Lenderking, the US special envoy for Yemen, told a Senate subcommittee that Iran鈥檚 clerical state was 鈥渆quipping and facilitating鈥� the Houthi attacks, which have triggered retaliatory US and British strikes on Yemen.

鈥淐redible public reports suggest a significant number of Iranian and Lebanese Hezbollah operatives are supporting Houthi attacks from inside Yemen,鈥� Lenderking said.

鈥淚 can鈥檛 imagine the Yemeni people want these Iranians in their country. This must stop,鈥� he said.

The White House said in December that Iran was 鈥渄eeply involved鈥� in planning the attacks, which the Houthis say are acts of solidarity with the Palestinians in the Israel-Hamas war.

Lenderking, who has dealt with the Houthis since the start of President Joe Biden鈥檚 administration as he helped diplomacy to freeze a brutal civil war, acknowledged that the rebels have not been deterred.

鈥淭he fact that they continue this, and have said publicly that they will not stop until there鈥檚 a ceasefire in Gaza, is an indication that we鈥檙e not yet at the point, unfortunately, where they do intend to dial back,鈥� Lenderking said.

The bombing campaign drew skepticism from some senators from Biden鈥檚 Democratic Party.

Chris Murphy, who heads the Senate Foreign Relations subcommittee on Middle East, agreed that the United States has 鈥渁n obligation to respond鈥� to attacks on shipping but added, 鈥淚 do worry about the efficacy.鈥�

The Houthis, who control war-torn Yemen鈥檚 most populated areas, have previously reported the death of 17 fighters in Western strikes targeting their military facilities.

The Houthi attacks have had a significant effect on traffic through the busy Red Sea shipping route, forcing some companies into a two-week detour around southern Africa.

Last week, Egypt said Suez Canal revenues were down by up to 50 percent this year.