When Joe Biden and Vladimir Putin meet for the first time as presidents in Geneva next week, Syria will be on the agenda. If the two leaders make progress on humanitarian aid there, that could send a positive signal regarding cooperation between the two countries and raise hope for millions of suffering people. But if Putin insists on starving the Syrian people, Biden must step in to help them.

More than 3 million Syrians, most of them internally displaced refugees, are massed in the northwestern province of Idlib. They are hungry and desperate, constantly dodging bombs dropped by the Syrian regime and the Russian military. Syrian President Bashar al-Assad, along with his Russian and Iranian partners, is perpetrating many war crimes, but the most vicious is their use of hunger and starvation as a weapon of war, which they are using to try to break the will of Syrians still resisting Assad’s cruel rule in this, the eleventh year of the Syrian revolution.

Disgracefully, Moscow is now threatening to cut off the last cross-border humanitarian aid route that supplies critical food and medicine to the parts of Syria that Assad doesn’t control. If Russia doesn’t agree by July 10 to reauthorize the U.N. Security Council resolution endorsing this aid route from Turkey — called Bab al-Hawaaid groups warn that millions of already desperate people will be condemned to a horrifying fate.

“The cruelty of closing the final humanitarian border crossing into Syria would be incalculable,” said Linda Thomas-Greenfield, the U.S. ambassador to the United Nations, during a visit to Turkey last week. “What I was told by the international NGO community and by the refugees themselves is that without this border crossing, they will die.”

The border-crossing issue in Syria will be on the agenda of the Biden-Putin summit in Switzerland, multiple senior White House officials told me. The administration has been engaging directly on it with the Russian government at various levels. Secretary of State Antony Blinken pressed Russian Foreign Minister Sergei Lavrov on the issue at their Reykjavik meeting last month. At a gathering of the U.N. Security Council in March, Blinken urged Russia to reauthorize the aid route and restore two others that Moscow had already worked to shutter.

“Unhindered access to Syrians is more important than ever — not only because of the growing humanitarian crisis, but also because of the threat posed by covid-19,” the secretary said.

The Biden team’s agenda for the Putin meeting in Switzerland is very crowded. But with the U.N. deadline approaching, the Syria part of the meeting represents a key test for both sides. Is Putin willing to strike a deal that could form the basis for further Syria-related cooperation? And is the Biden administration willing to make this issue a priority and really press (rather than bribe) the Russians into doing the right thing?

“It’s a clarifying moment,” said Brian Katulis, a senior fellow at the Center for American Progress. “How the United States and Russia deal with the Syria issue clarifies not only what Putin’s stance is, but it will also reveal how committed the Biden administration is to elevating human rights and democracy as a priority in its foreign policy.”

Publicly, Moscow’s position has been that humanitarian aid should all flow through the Assad regime, an absurd proposition considering that Assad is the one intentionally starving Idlib in the first place. Behind the scenes, U.S. officials believe Moscow is looking for sanctions relief from Biden in exchange for reauthorizing the aid route, but that would amount to rewarding Putin for not starving civilians — a grotesque notion.

If Putin rebuffs Biden and won’t allow the humanitarian aid routes to continue, the United States and its partners, including Turkey, would face an enormous challenge in working outside the U.N. system to deliver aid to Idlib. But that’s a reality the United States must prepare for now. And these preparations also serve to increase Washington’s leverage vis-a-vis Moscow.

Biden’s actions on Syria in Geneva will also be a litmus test for how the United States will resist Russian and Chinese expansion in the region. That is a point made by the leaders of Senate Foreign Relations and House Foreign Affairs committees in a letter to Blinken this week. They urged him to apply high-level engagement and pressure on Moscow and Beijing.

“Russia’s campaign to eliminate cross-border humanitarian aid deliveries is part of a larger effort to maintain eastern Mediterranean access, encourage the international community to rehabilitate the Assad regime, and open the door to reconstruction funding that will entrench the Assad regime in power and secure Russia’s strategic foothold,” the letter stated.

Focusing American diplomatic power and attention on Syria might seem like a distraction for the Biden team as it seeks to shift money and resources away from the Middle East toward a great-power competition with Russia and China. But great-power competition takes place all over the world, including in the Middle East. The Biden administration can’t afford to ignore that.

Nor can the United States ignore millions of innocent people starving unnecessarily on our watch. The Biden team is saying the right things about Syria, but actions speak louder than words.

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