Elon Musk has prompted an online row with Ukraine’s president after he asked Twitter users to weigh in on his ideas to end Russia’s war.

In a tweet, Musk suggested UN-supervised elections in four occupied regions that Moscow has falsely annexed after what it called referendums. The votes were denounced by Kyiv and western governments as illegal and coercive. “Russia leaves if that is will of the people,” Musk wrote.

The Tesla chief executive also suggested that Crimea, which Moscow seized in 2014, be formally recognised as Russia, that water supply to Crimea be assured, and that Ukraine remain neutral. He asked Twitter users to vote yes or no to his idea.

The tweet infuriated Ukrainians, and President Volodymyr Zelenskiy responded with his own poll.

“Which @elonmusk do you like more?,” Zelenskiy tweeted, offering two responses: one who supports Ukraine, or supports Russia.

The Ukrainian presidential aide Mykhaylo Podolyak suggested a “better peace plan” under which Ukraine took back its territories including Crimea; Russia was demilitarised and denuclearised; and “war criminals” faced an international tribunal.

Ukraine’s outspoken outgoing ambassador to Germany, Andriy Melnyk, had a blunt reaction.

“Fuck off is my very diplomatic reply to you @elonmusk,” tweeted Melnyk.

Other European leaders also voiced their opposition to Musk’s plan.

“Dear @elonmusk, when someone tries to steal the wheels of your Tesla, it doesn’t make them legal owner of the car or of the wheels. Even though they claim both voted in favour of it. Just saying,” Lithuania’s president, Gitanas Nausėda, tweeted in response.

Musk, who is also chief executive of SpaceX, followed up his first tweet with another poll: “Let’s try this then: the will of the people who live in the Donbas & Crimea should decide whether they’re part of Russia or Ukraine.”

He said he didn’t care if his proposal was unpopular, arguing that he did care “that millions of people may die needlessly for an essentially identical outcome”.

In February, when Ukraine’s internet was disrupted following Russia’s invasion, Musk responded to a tweet by a Ukrainian government official seeking help. Musk said SpaceX’s Starlink satellite broadband service was available in Ukraine and that SpaceX was sending more terminals.

With Reuters and Agence France-Presse