The tempest started when the Tesla CEO proposed a “peace” plan for the war in Ukraine that consisted of four suggestions, including that Crimea—which was invaded by Russia in 2014 and is currently occupied by it—formally becomes part of Russia, and Ukraine doesn’t join NATO. (As of 10:00 a.m. ET, more than 2.6 million people have voted in his yes/no poll to the plan, with 59.4% opposing his suggestion.)

Kremlin spokesman Dmitry Peskov told the Russian news agency Interfax it was “very positive that a person like Elon Musk is looking for a peaceful way out of the situation,” adding that Musk’s ideas “deserve attention.”

That reaction is in stark contrast to what Ukraine’s ambassador to Germany, Andrij Melnyk, had to say to Musk: “F— off is my very diplomatic reply to you,” he replied via Twitter.

Putin invaded in Ukraine in February of this year, in a move that was widely condemned. Russia was quickly hit with major economic sanctions from Western countries, and the U.S and Europe have rallied behind Ukraine, sending billions in aid, along with weapons.

“This is highly likely to be the outcome in the end—just a question of how many die before then,” Musk wrote in subsequent posts. “Also worth noting that a possible, albeit unlikely, outcome from this conflict is nuclear war.”

Musk’s proposal also drew the ire of Ukrainian president Volodymyr Zelensky, who set up his own poll, asking “Which @elonmusk do you like more: One who supports Ukraine [or] one who supports Russia.”

Of the 2.3 million votes on that poll, 79% said they would prefer that Musk support Ukraine.

While Musk ignored Melnyk, Zelensky’s rebuke caught his attention and coaxed a reply. “I still very much support Ukraine, but am convinced that massive escalation of the war will cause great harm to Ukraine and possibly the world,” he tweeted.

Ukraine has insisted it will not cede any of its territory to Russia and has also applied to join NATO. Tuesday, Ukrainian troops forced Russian troops into retreat on two fronts in the east and south.