Russia's foreign minister said Friday that no summit is planned between President Vladimir Putin and Ukrainian President Volodymyr Zelenskyy, undercutting President Donald Trump's push for a high-level meeting aimed at ending the war.

"Putin is ready to meet with Zelenskyy when the agenda is ready for a summit, and this agenda is not ready at all," Foreign Minister Sergey Lavrov told NBC News' Meet the Press moderator Kristen Welker in an interview. "President Putin said clearly that he is ready to meet provided this meeting is really going to have an agenda, presidential agenda."

The Biden White House had spent months working on a summit plan, but Trump revived the effort after his Aug. 15 meeting with Putin in Alaska and subsequent discussions with Zelenskyy and European leaders in Washington. Despite those efforts, Moscow has signaled little urgency and on Thursday launched its largest aerial assault since early July, striking multiple cities across Ukraine.

Lavrov said Trump had outlined proposals in Anchorage that Russia considered flexible, including guarantees of no NATO membership for Ukraine and talks on territorial questions. "When President Trump brought ... those issues to the meeting in Washington, it was very clear to everybody that there are several principles which Washington believes must be accepted, including no NATO membership, including the discussion of territorial issues, and Zelenskyy said no to everything," Lavrov stated.

"He even said no to, as I said, to canceling legislation prohibiting the Russian language. How can we meet with a person who is pretending to be a leader?" Lavrov added. Ukraine has not banned Russian, though Moscow has long claimed, without evidence, that Kyiv discriminates against Russian speakers.

Zelenskyy accused Moscow of stalling. Russia is trying to "wriggle out" of holding a meeting, continuing massive attacks on Ukraine, he said Thursday. The Ukrainian president emphasized he was "ready" to meet Putin and urged "a strong reaction from the United States," including tougher sanctions and economic pressure, if Russia refuses.

Russia's latest assault involved nearly 600 drones and 40 ballistic and cruise missiles, according to Ukrainian officials. One target was a U.S.-owned Flex electronics factory in western Ukraine, where at least 15 workers were injured.

Trump reacted to the strikes on Truth Social, writing: "There is no chance of winning!" He compared Ukraine's position to a sports team with "a fantastic defense, but is not allowed to play offense." Zelenskyy agreed, saying Trump was "absolutely right" that Ukrainians needed more than defensive protection, though he stressed that diplomacy remained Kyiv's primary focus.

Meanwhile, Western governments advanced talks on long-term security guarantees for Ukraine. Defense chiefs from the U.S., U.K., France, Germany, Italy, Finland and Ukraine met this week to draft options that will now go before national security advisors. Trump has said the U.S. would provide guarantees in a settlement but ruled out sending American ground troops, suggesting instead that support could include air power.

Lavrov said Moscow was not opposed to such talks but warned against excluding Russia from the process. Any attempt to develop guarantees without Russia, he said, would be "a utopia, a road to nowhere."