The US has moved to delist Yemen's Huthi rebels as terrorists, removing a block that humanitarian groups said jeopardized crucial aid, as the country's warring sides welcomed a push for peace from new president Joe Biden.

The grinding six-year war in Yemen has killed tens of thousands and displaced millions, triggering what the United Nations calls the world's worst humanitarian disaster.

"We have formally notified Congress of the secretary's intent to revoke these designations," a State Department spokesperson said Friday.

The move, which will take effect shortly, comes a day after President Joe Biden announced an end to US support for Saudi-led offensive operations in Yemen in his first major foreign policy speech since replacing Donald Trump.

Yemeni tribesmen attend a rally denouncing the US designation of the Huthi rebels as a terrorist group in the Huthi-held capital Sanaa on February 4, 2021
Yemeni tribesmen attend a rally denouncing the US designation of the Huthi rebels as a terrorist group in the Huthi-held capital Sanaa on February 4, 2021 AFP / Mohammed HUWAIS

"This decision has nothing to do with our view of the Huthis and their reprehensible conduct, including attacks against civilians and the kidnapping of American citizens," the spokesperson said.

"Our action is due entirely to the humanitarian consequences of this last-minute designation from the prior administration," they added.

Aid groups say they have no choice but to deal with the Huthis, who are the de facto government in much of Yemen, and that the terrorist designation would put them at risk of prosecution in the United States.

Blinken's predecessor Mike Pompeo announced the designation days before leaving office last month, pointing to the Huthis' links to Iran, an arch-enemy of Trump, and a deadly attack on the airport in Yemen's second city of Aden in December.

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