MUNICH — At the high-profile Munich Security Conference Saturday, Ukrainian President Volodymyr Zelenskyy drummed up international support for Ukraine’s ongoing war with Russia, saying that U.S. Senators and world leaders must understand that a win for Russia in Ukraine would have repercussions beyond its borders.

Zelenskyy’s rallying cry came in the wake of fresh outrage among world leaders over the death of prominent Russian opposition figure, Alexei Navalny while in custody at a Siberian prison on Friday, and Ukraine’s withdrawal this week from Avdiivka, a key battleground on the front against Russia.

Calling for the restoration of “rules based world order,” Zelenskyy described Russia’s invasion as a “war against any rules at all.”

Zelenskyy was met with an extended standing ovation as he called for the world to “act now” to oppose Russia, using his floor time to renew support for his country’s long and largely stalemated defense against Russia, as attention turned in recent months to the Israel-Gaza war.

He pressed for more artillery and long-range weapons before the audience of security officials from the U.S., E.U., China and the Middle East.

“Ukrainians have been holding for 724 days,” he said to loud applause as he promised that Ukraine could get its land back and win the war against Russia.

Ukrainian forces withdrew from the key town of Avdiivka this week in the most high-profile retreat for the country since its withdrawal from the city of Bakhmut last May.

The retreat from Avdiivka came amid delays in new U.S. military aid to Ukraine, which has been stalled in Congress for months due to growing Republican opposition.

Zelenskyy is slated to meet with Vice President Kamala Harris Saturday, who is expected to restate the government’s commitment to Ukrainian security.

Calling on leaders to do “everything necessary” to protect Ukraine, Zelenskyy said a failure to act would mean that Russian leaders beyond Putin would “remember how to maintain power.”

The death of Alexei Navalny in jail was not just another episode in a long history of Putin’s eradication of his foes, he said, but a direct message to everyone at the Munich Security Conference.

“There is no one for whom the ongoing war in Europe does not pose a threat,” he said. “This war defines more than just the place of Ukraine or entire Europe in the world.”

Navalny, an outspoken critic of Putin’s war with Ukraine, went missing in Russia’s penal system in December while serving a 30 ½-year jail sentence, eventually turning up at a high-security penal colony in a remote town above the Arctic Circle.

He died after feeling unwell following a walk Friday, the Russian Federal Penitentiary Service said in a statement.

Responding to the death of Navalny Friday, President Joe Biden said he “hope[d] to God it helps” push Congress into approving further support for Ukraine.

His comments came as House Speaker Mike Johnson convened an early recess for Congress on Friday, without approving a $95 billion Defense Department package which includes over $60 billion for Ukraine.

“The failure to support Ukraine at this critical moment will never be forgotten,” Biden said, adding that reticence on Ukraine was reinforcing global fears about whether the U.S. was a responsible ally.