President Joe Biden's administration on Monday froze US sanctions on dealing with Yemen's Huthi rebels for one month as it reviews a terrorist designation that aid groups warn will aggravate a humanitarian crisis.

The Treasury Department in a notice said that all transactions with the group will be authorized through February 26 at 12:01 am (0401 GMT).

The order signed by Bradley Smith, acting director of the Office of Foreign Assets Control, said the United States was not unblocking any funds that have already been targeted.

The move comes after Antony Blinken, Biden's choice for secretary of state, said that the United States would quickly review the designation of the Huthis as a terrorist group and end military support to Saudi Arabia's bloody offensive in Yemen.

Former president Donald Trump's administration, closely allied with the Saudis and vociferously opposed to Iran, declared the Tehran-aligned group to be terrorists in a determination that took effect on January 19 -- one day before Biden's inauguration.

Trump's secretary of state, Mike Pompeo, announced the move despite months of warnings by aid groups that the decision would intensify suffering in a nation where more than 80 percent of the 29 million people need aid to survive.

Humanitarian groups argue that they have no alternative but to deal with the Huthis, who amount to a government in much of Yemen including the capital Sanaa.

Pompeo had insisted that the State Department was exempting humanitarian work, but Blinken said the effort was not enough as it pertained just to Americans.

The Treasury Department in revised guidance said that non-US entities would not be targeted.

Tens of thousands have died and millions displaced in Yemen's six-year civil war as the Saudis fight to dislodge the Huthis and prop up a fledgling internationally recognized government.

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