Saudi Arabia has proposed a peace deal to end the nearly six-year war in Yemen, if the Iranian-backed Houthi rebels agree.

The Saudi proposal calls for a nationwide ceasefire and reopening the airport in the Yemeni capital, Sanaa.

"The initiative aims to end the human suffering of the brotherly Yemeni people, and affirms the Kingdom's support for efforts to reach a comprehensive political resolution," the Saudi Foreign Ministry said in a statement.

The war has been a quagmire for the Saudis and they are apparently looking for a way out. In response to the initiative, the Houthis said it provided "nothing new," Reuters reports, as the proposal does not include a complete lift of the blockade on Sanaa's airport or the port city of Hodeidah.

"We expected that Saudi Arabia would announce an end to the blockade of ports and airports and an initiative to allow in 14 ships that are held by the coalition," the Houthis' chief negotiator, Mohammed Abdulsalam, told Reuters.

"Opening the airports and seaports is a humanitarian right and should not be used as a pressure tool," he said.

The United States and the U.N. have been trying to end what they call the world's worst humanitarian disaster. President Biden has pledged to use diplomacy to end the war and to allow more refugees to come to the U.S.

In a briefing, U.N. spokesperson Farhan Haq said he welcomed the Saudi proposals, and that U.N. envoy Martin Griffiths has been working toward these goals. Asked about the Houthis' rejection of the Saudi offer, Haq said Griffiths would be in touch with all parties to discuss moving forward with Saudi Arabia's proposal.

Peter Salisbury, senior Yemen analyst at the International Crisis Group, says the Saudi proposal is essentially anew take on an idea that was put forth a year ago.

"The devil is still in the details. The Saudis, the government and the Huthis all say they support the initiative in concept terms but have quibbled incessantly over timing, sequencing and the details of each aspect," Salisbury wrote in a thread on Twitter.

Salisbury says he believes the Saudi proposal is likely aimed at pressuring the Houthis. For now, he predicts more talks, more air strikes, and more fighting on the ground: "We're in a period where the parties are using all tools at their disposal to improve their bargaining position."

The conflict has become a proxy war between Saudi Arabia and Iran. Years of fighting have left 80% of Yemen's population reliant on aid and millions are on the brink of starvation.

The war in Yemen began in 2014, when Houthi militants supported by Iran overthrew the unpopular Saudi-backed government in Yemen's capital. A coalition of Gulf states — led by Saudi Arabia and with support from the U.S., France and the U.K. — responded with airstrikes, beginning in 2015.

While the Biden administration has been critical of the way the Saudis have waged the war, it has also raised alarms about recent Houthi attacks against Saudi Arabia.

The State Department said that in a call with Saudi Arabia's foreign minister, U.S. Secretary of State Antony Blinken "reiterated our commitment to supporting the defense of Saudi Arabia and strongly condemned recent attacks against Saudi territory from Iranian-aligned groups in the region."

The two officials reportedly expressed support for diplomatic efforts to end the conflict in Yemen, "starting with the need for all parties to commit to a ceasefire and facilitate the delivery of humanitarian aid."

State Department deputy spokesperson Jalina Porter said the proposal is "one step in the right direction," calling on all of the parties to negotiate under the auspices of the U.N.

NPR Diplomatic Correspondent Michele Kelemen contributed to this report.

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