U.S. Central Intelligence Agency Director John Ratcliffe made a surprise trip to Moscow this week to warn Russia against attacking NATO, according to multiple media reports, amid growing fears of further escalation in the Ukraine war.

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Ratcliffe’s first publicly known visit to the Russian capital as CIA chief came to light on Tuesday, when a U.S. Air Force jet was spotted arriving at a Moscow airport, and footage of a diplomatic motorcade moving through the city emerged on social media.

The purpose of Ratcliffe’s trip to the Russian capital was first reported Wednesday by the Wall Street Journal, citing unnamed sources briefed on the trip.

Politico and CBS News separately reported the same motive, citing multiple people familiar with the matter. CBS News added that Ratcliffe also brought up Iran, warning of additional sanctions if the strategically vital Strait of Hormuz does not reopen to shipping traffic.

The Trump administration has threatened Iran’s trading partners with so-called secondary sanctions as it seeks to ratchet up the pressure on Tehran’s economy following six months of war between the U.S., Israel and Iran.

China, the United Arab Emirates and Turkey are known to be among Iran’s top trading partners, while Russia has long shared close economic and military ties with Tehran.

Spokespeople for the CIA and the Russian Embassy in London were not immediately available to comment when contacted by CNBC.

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Russia and Ukraine have exchanged an intensifying series of drone and missile strikes far beyond the front lines in recent weeks, amplifying fears of further escalation in the conflict.

Alongside analysts and external observers warning that Russia’s full-scale invasion could soon enter a more dangerous phase, Ukrainian President Volodymyr Zelenskyy has said that Russian President Vladimir Putin is preparing to escalate the war.

In comments posted on X earlier this month, Zelenskyy called on the country’s partners to ramp up sanctions pressure on Moscow and provide Kyiv with further air defense support.

Russian forces have increased the number of missile strikes on Ukrainian cities in recent weeks, likely as part of a push to exploit Kyiv’s shortage of ballistic missile interceptors.

Zelenskyy has repeatedly called on international partners to expedite the supply of ballistic missile interceptors to Ukraine, saying the technology could have saved the lives of those killed in Kyiv on Aug. 5.

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