(AP)

European Union held a summit Thursday focused on preventing a Russian military invasion of neighboring Ukraine with threats of unprecedented sanctions for Moscow and the promise of diplomatic talks.

And on a day of diplomatic moves, Russia said it submitted draft documents to the United States outlining security arrangements that would preclude NATO’s expansion to Ukraine.

A Russian military buildup on Ukraine’s border took center stage at the summit of the EU’s 27 leaders, coming on the heels of a plea from Ukraine’s president for more sanctions to be imposed before any possible incursion instead of after.

Lithuanian President Gitanas Nauseda said the EU should not underestimate the threat Russia’s troop buildup poses, adding that he sees Moscow’s actions as creating the worst security situation since the collapse of the Soviet Union.

“I’m talking not only about Ukraine,” Nauseda said, stressing that NATO’s eastern flank and the Baltic region should also be concerned.

German Chancellor Olaf Scholz warned Moscow not to cross any lines.

“The inviolability of borders is one of the very important foundations of peace in Europe and that we will all do everything together to ensure that this inviolability actually remains intact,” Scholz said as he entered the one-day summit.

Many of the leaders said they looked toward diplomatic talks to stave off military action in Ukraine. Prime Minister Janez Jansa of Slovenia, which holds the EU’s rotating presidency until the end of the year, suggested talks between France, Germany, Ukraine and Russia.

“Maybe there are some open channels for some serious negotiations” over the coming days, Jansa said.

Moscow denies that it has any plans to attack Ukraine, but did so in 2014 when it annexed the Crimean Peninsula. U.S. intelligence officials say Russia has moved 70,000 troops and is preparing for a possible invasion early next year.

“It is not normal for regular military exercises,” Jansa said, adding that there’s no doubt that Russia is using its military might to put Ukraine under pressure.

Related News

Ukrainian President Volodymyr Zelenskyy urged EU leaders late Wednesday to swiftly impose new sanctions on Russia before it invades his country, warning that acting after any conflict would be far too late.

Zelenskyy said Ukraine stands ready to enter into talks with Russia to ease tensions but that Russian President Vladimir Putin doesn’t appear willing to come to the table at the moment.

France and Germany brokered a peace agreement in 2015 that helped end large-scale hostilities in eastern Ukraine, where Ukrainian forces have been fighting Russia-backed separatists since 2014. But the conflict, which has left 14,000 dead, has simmered.

EU leaders are widely expected to approve on Thursday a draft summit conclusion, seen by The Associated Press, that warns that “any further military aggression against Ukraine will have massive consequences and severe cost in response.”

European officials argue that it’s a better deterrent to keep Putin in the dark about what measures might be used against him.

Asked by reporters whether Europe would act on Zelenskyy’s call, European Council President Charles Michel said: “We have sanctions in place, we are ready to take additional sanctions if needed, and we will see” what happens.

Despite Moscow’s threat, Nauseda still has a sense of optimism.

“I think we have enough tools in order to stop Russia from its aggressive behavior,” he said.

The U.S. and the EU have been coordinating their response to the Russians, but no real details of any sanctions have emerged.

The Kremlin on Thursday again prodded Western leaders to provide legally binding guarantees precluding NATO’s expansion to Ukraine and the deployment of the alliance’s weapons there, calling such moves a “red line” for Moscow.

The U.S. and its allies have refused to make such a pledge, but Putin and U.S. President Joe Biden agreed last week on further talks to discuss Russian concerns.