WASHINGTON – Secretary of State Mike Pompeo on Tuesday ratcheted up his push for an end to the deadly war in Yemen – a devastating and increasingly controversial conflict that has severely tested the U.S. relationship with Saudi Arabia and created the world’s worst humanitarian disaster.

“It is time to end this conflict … and allow the Yemeni people to heal through peace and reconstruction,” Pompeo said in a statement Tuesday night.

The war is essentially a proxy battle between Saudi Arabia and Iran. The U.S. has provided military support for a Saudi-led bombing campaign aimed at defeating the Houthi rebels, who are backed by Iran and who helped oust Yemen’s former president in 2015.

The Trump administration has come under intense pressure to curb its support of the Saudi-led coalition, as civilian casualties have mounted and a horrific humanitarian disaster has unfolded. The war in Yemen has killed or injured at least 17,000 civilians and put an estimated 8 million Yemenis on the brink of starvation.

A growing number of lawmakers in Congress have pressed the Trump administration to withdraw U.S. military support for the war – an effort that gained fresh momentum in the wake of Saudi Arabia’s role in the murder of Jamal Khashoggi, a Washington Post columnist and U.S. resident.

Robert Palladino, a State Department spokesman, denied that the Khashoggi case had intensified pressure on the Trump administration to resolve the Yemen conflict.

"They're unrelated," Palladino told reporters during a State Department briefing Wednesday.

Pressed about the timing of Pompeo's statement, he said, "we've seen progress being made on the ground" and argued "the climate is right for both sides to come to the table." But he declined to elaborate on what made this moment ripe for a political resolution.

But Eric Eikenberry, an advocacy officer with the Yemen Peace Project, said he thinks Pompeo issued Tuesday's forceful statement on Yemen because he fears what may come next.

"I think the administration is finally realizing that, if the war continues at its current level of violence and Yemenis suffer a massive famine, the U.S. will be seen as directly culpable," Eikenberry said.

U.N. officials have told the U.S. and other foreign leaders "that they've exhausted their capacity to stabilize the crisis and will be unable to prevent or otherwise curtail a famine if one occurs in coming months," he added. "Given this climate, the administration wants to look like its getting out front of the issue before the humanitarian situation deteriorates further."

Still, he and others noted that Pompeo’s statement was carefully worded. He called on the Houthi rebels to stop their attacks on Saudi Arabia first – and then on the Saudi-led coalition to stop bombing population centers in Yemen.

“The time is now for the cessation of hostilities, including missile and UAV strikes from Houthi-controlled areas into the Kingdom of Saudi Arabia and the United Arab Emirates,” Pompeo said. “Subsequently, coalition air strikes must cease in all populated areas in Yemen.”

Pompeo also urged the warring parties to support a United Nations-led effort to broker a political resolution to the war – an effort that has proved unsuccessful over three years of bloody conflict.

Pompeo’s remarks echoed a similar statement from Defense Secretary Jim Mattis on Tuesday. In remarks at the Washington-based U.S. Institute of Peace, Mattis urged a cease-fire within 30 days.

"The longer-term solution, and by longer-term, I mean 30 days from now, we want to see everybody sitting around the table, based on a ceasefire, based on a pullback from the border, and then based on ceasing dropping of bombs,” Mattis said, according to CBS News. Mattis said that would allow the U.N.’s special envoy on Yemen, Martin Griffiths, to forge a political settlement.

In an interview Wednesday with the BBC, Griffiths said he welcomed the vocal support for a political resolution from Pompeo and Mattis. He said both the Saudis and the Houthis have signaled an interest in deescalating the conflict.

"It’s not necessarily going to be easy to have a full cease-fire, as has been called for," he told the BBC, "but measures moving in that direction … would be most welcome."

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