"F*** off is my very diplomatic reply to you," said Andriy Melnyk, Ukraine's ambassador to Germany.
ADVERTISEMENTBillionaire businessman Elon Musk has been strongly criticised after posting a series of Tweets about Russia's invasion of Ukraine.
Ukraine's President Volodymyr Zelenskyy and Foreign Minister Dmytro Kuleba are among the most prominent politicians who responded to the online comments.
On Monday evening, Musk tweeted about the conflict to his 107.7 million followers, telling them first that to achieve peace between Ukraine and Russia there should be a "redo" of what he labelled as "elections" -- referring to the sham referendums -- "under UN supervision" in four areas of eastern Ukraine illegally annexed by Russia.
Musk said "Russia leaves" those areas "if that is the will of the people".
He also said that Crimea, illegally annexed by Russia in 2014, should become "formally part of Russia, as it has been since 1783 (until Khrushchev's mistake)", referencing the 1954 decree issued by then-Soviet premier Nikita Khrushchev to transfer responsibility for Crimea to the Ukrainian Soviet Socialist Republic.
The line about Crimea being part of Ukraine was "Krushchev's mistake" has long been a Kremlin talking point.
Crimea held a referendum in 1991 on its independence as a distinct socialist republic within the Soviet Union, largely favouring being a part of the newly-independent Ukraine instead.
In 1996, the peninsula adopted a new constitution, amending it to reflect its status as a highly autonomous region within Ukraine.
Moscow recognised Crimea as Ukrainian by signing the 1997 Friendship Treaty between Ukraine and Russia.
Tesla boss Elon Musk also said that Ukraine must "remain neutral," and in later tweets said, "victory for Ukraine is unlikely".
What has the reaction been like?
In response to Musk's tweets, Zelenskyy posted a Twitter poll asking "which Elon Musk do you like more?" with the options being "one who supports Ukraine" or "one who supports Russia."
Ukraine's foreign minister was even more vociferous in his response to Musk, although he did not mention the South African-born businessman directly by name.
"Those who propose Ukraine give up on its people and land — presumably not to hurt Putin’s bruised ego or to save Ukraine from suffering — must stop using the word “peace” as a euphemism to “let Russians murder and rape thousands more innocent Ukrainians, and grab more land,” Kuleba said.
Ukraine's ambassador to Germany was also undiplomatically direct in his response to Musk's comments saying "fuck off is my very diplomatic reply to you", and writing that "the only outcome is that now no Ukrainian will EVER buy your f…ing tesla crap. So good luck to you".
The overwhelming majority of the reactions on Twitter to Musk's comments about Ukraine have been negative, with a number of responses advising him not to comment on things he apparently knows very little about.