Poland and Lithuania called Monday for more severe sanctions from the West against Russia over the buildup of troops at Russia's border with Ukraine.
Ukraine has made similar requests of its allies in recent weeks as U.S. intelligence says around 70,000 Russian troops are near the Ukrainian border, fueling concerns of a potential invasion poised to take place in 2022, a possibility that Moscow has denied.
Ukrainian President Volodymyr Zelensky met with Polish President Andrzej Duda and Lithuanian President Gitanas Nauseda on Monday in Ukraine as Russia continues to demand that Ukraine be denied entry into NATO and for Ukraine's allies to scale back their military support of the nation.
"Our common task is to deter the threat posed by Russia and defend Europe from Russia's aggressive policies," Zelensky said after the meeting. "Ukraine, Poland and Lithuania are the vanguard of that deterrence today."
He called for "powerful preventative actions, powerful serious sanctions to exclude any thought about escalation."
In a joint statement, Zelensky, Duda and Nauseda "called upon the international community to step up sanctions on the Russian Federation over its ongoing aggression against Ukraine and once again urged the Kremlin to de-escalate the situation by withdrawing its troops from the Ukrainian border and temporarily occupied territories."
Duda also emphasized that Russia's actions have gone too far and now is not the time to concede to its demands.
"I'm categorically against making any concessions to Russia," Duda said. "It's clear that it's Russia which must step back."
Russia annexed Ukraine's Crimean Peninsula in 2014 and, shortly afterward, cast its support behind a separatist rebellion in the country's east. More than seven years of fighting has killed over 14,000 people and devastated Ukraine's industrial heartland, known as the Donbas.
Nauseda emphasized that any attempts by Russia to draw "red lines" are "unacceptable in Europe in the 21st century."
Moscow on Friday published draft security documents demanding that NATO deny membership to Ukraine and other former Soviet countries and roll back the alliance's military deployments in Central and Eastern Europe—bold ultimatums that are almost certain to be rejected by the U.S. and its allies.
Russian President Vladimir Putin raised the demand for security guarantees in last week's video call with U.S. President Joe Biden, who warned that Russia would face "severe consequences" if Moscow attacked its neighbor.
Russian diplomats have said that Moscow will have to up the ante if its demands are rejected.
Russian Deputy Foreign Minister Alexander Grushko warned that Moscow will respond in kind if NATO deploys missiles capable of reaching Russia in a few minutes.
"If offensive weapons capable of reaching our control centers appear on the territory of NATO members, we will have to create a similar situation for our counterparts," Grushko told the daily newspaper Rossiyskaya Gazeta.
The Associated Press contributed to this report.
