The calls from the United Nations three top officials come after US Secretary of State Mike Pompeo declared the Iran-linked Houthis a “foreign terrorist organisation.”
Three top United Nations officials have called on the United States to revoke its decision to designate Yemen's Houthis a foreign terrorist organisation, warning it would push the country into a large-scale famine and chill peace efforts.
UN Yemen mediator Martin Griffiths, UN aid chief Mark Lowcock and UN food chief David Beasley issued their warnings during a UN Security Council meeting on Yemen.
"We fear that there will be inevitably a chilling effect on my efforts to bring the parties together," Griffiths told the 15-member body.
"The decision will contribute to the prospect of famine in Yemen and should be revoked based on humanitarian grounds at the earliest opportunity."
The United Nations describes Yemen as the world's largest humanitarian crisis, with 80 percent of the people in need of aid.
US Secretary of State Mike Pompeo announced the move against the Iran-aligned Houthis on Sunday. It will come into effect on January 19, the last full day in office of President Donald Trump's administration.
President-elect Joe Biden takes office on January 20. The designation could be revoked by Biden's administration.
'It's going to be catastrophic'
"We are struggling now without the designation. With the designation, it's going to be catastrophic. It literally is going to be a death sentence to hundreds of thousands, if not millions of innocent people in Yemen," said Beasley, a former governor of South Carolina.
"This designation - it needs to be reassessed, it needs to be reevaluated. And quite frankly, it needs to be reversed," he said.
While the United Nations and aid groups help about a third of Ye men's 28 million people, Lowcock stressed commercial imports are key to ensuring millions more have access to food.
He said a US plan to issue licenses and exemptions to allow aid agencies to continue working will not prevent a famine in Yemen, which relies almost solely on imports.
"Aid agencies cannot – they simply cannot - replace the commercial import system," said Lowcock, warning the US decision would push Yemen into a "famine on a scale that we have not seen for nearly 40 years."
"What would prevent it? A reversal of the (US) decision," he said.
The designation freezes any US-related assets of the Houthis, bans Americans from doing business with them and makes it a crime to provide support or resources to the movement.
Beasley also raised the alarm on a massive shortfall in aid funding for Yemen. He called on "the Gulf states, the Saudis to pick up the financial tab for the needs inside Yemen because the needs in other parts of the world are so great."
ICRC raises concern
The International Committee of the Red Cross has said that it feared that the US move would lead to a "chilling effect" on delivering vital aid to sick and starving civilians.
ICRC director of operations Dominik Stillhart said on Thursday that the independent agency has urged states imposing such measures to consider "humanitarian carve-outs" to mitigate any negative impact on populations and on impartial aid.
Stillhart said the ICRC was increasingly alarmed at the humanitarian situation in Yemen – where it has its second largest operation worldwide – as infectious diseases, hunger and rising food prices hit civilians.
The statement was issued on his return from the country after three ICRC staff were killed in an attack on Aden airport on December 30.
"In particular, the ICRC is concerned about the possible 'chilling effect' the designation may have on humanitarian action, leading to it being impeded or delayed," he said.
"Increased operational risks and possible de-risking from the banking and private sectors in response to the designation ultimately may constrain the humanitarian response in Yemen."
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Six years of war between a US-backed Arab coalition and the Houthi rebels have been catastrophic for Yemen, killing more than 112,000 people and wrecking infrastructure from roads and hospitals to water and electricity networks.
It began with the Houthi takeover of the north in 2014, which prompted a destructive air campaign by the Saudi-led coalition, aimed at restoring the internationally recognised government.
The Houthis, who receive financial and military support from Iran, rule the capital and Yemen’s north where the majority of the population lives, forcing international aid groups to work with them.
Agencies depend on the Houthis to deliver aid, and they pay salaries to Houthis to do so.
The US designation is part of the Trump administration’s broader effort to isolate and cripple Iran.
It also shows support to its close ally, Saudi Arabia, which leads the anti-Houthi coalition in the war.
Saudi Arabia advocated the terror designation, hoping it would pressure the rebels to reach a peace deal.
Past rounds of peace talks and ceasefire agreements have faltered.