Ukraine's ambassador to the U.N. in Geneva, Yevheniia Filipenko, led the walkout, which left a mostly empty conference hall to hear Lavrov's pre-recorded video message during the council's meeting on disarmament.

The Ukrainian envoy said that this action "sends a very strong signal" to Moscow that the Russian military's ongoing invasion and assault is "not acceptable."

Lavrov said that he had planned to attend the session in person but was unable to travel to Switzerland after the European Union banned flights from Russia.

According to the New York Times:

He accused Ukraine of seeking to acquire nuclear weapons, an unsubstantiated claim that Moscow has used as one of the justifications for its invasion. Ukraine gave up its Soviet-era nuclear arsenal in 1994 in exchange for security guarantees.

Mr. Lavrov repeated the Kremlin's assertions that Ukraine had "made territorial claims against the Russian Federation, threatened to use force and acquire a military nuclear capability." In earlier comments to the Conference on Disarmament, he said that Ukraine still possessed Soviet-era technology that would enable it to deliver such weapons, adding: "We cannot fail to respond to this real danger."

Speaking just two days after Russian President Vladimir Putin put his country's nuclear forces on special alert and one day after Belarus agreed to host Russian nuclear weapons, Lavrov said that the Kremlin believes a "nuclear war cannot be won and should never be fought"—repeating a phrase adopted by Putin and U.S. President Joe Biden at a July 2021 summit.