It was shared by the former US Secretary of State and Mr Trump’s 2016 presidential rival on Sunday afternoon with the caption: “Found in the archives…” “Dear Premier Khrushchev,” the letter started. “Don’t be a d***, ok? Get your missiles out of Cuba. Everybody will say ‘Yay! Khrushchev! You’re the best!’ But if you don’t, everyone will be like ‘what an a******’ and call your garbage country ‘The Soviet Bunion.’” The letter ended: “You’re really busting my n*** here. Give you a jingle later. Hugs, John Fitzgerald Kennedy.”
Mrs Clinton’s tweet mocked a real letter from the US President warning the Turkish leader not to “be a fool” over Syria.
In the missive released to the public last week, Mr Trump threatened to wreck Turkey’s economy if its invasion of Syria went too far.
He wrote: “You don’t want to be responsible for slaughtering thousands of people, and I don’t want to be responsible for destroying the Turkish economy – and I will.
“I’ve worked hard to solve some of your problems. Don’t let the world down.
“History will look upon you favourably if you get this done the right and humane way. It will look upon you forever as the devil if good things don’t happen.
“Don’t be a tough guy. Don’t be a fool!
Mr Trump concluded: “I will call you later.”
The note was widely criticised by Democratic politicians and savagely derided on social media for having been written at a “third-grade reading level” and being “embarrassing beyond words”.
“Honestly this letter from Trump to Erdogan would make more sense if it were written in crayon on lined practice paper rather than on White House letterhead,” tweeted Washington Post columnist Brian Klaas.
The White House was later forced to confirm the letter’s legitimacy after it was presumed to be a hoax.
Mr Trump was urging Turkey not to launch a military offensive against Kurdish-led forces in northern Syria, but Mr Erdogan ignored his request.
The Turkish President reportedly “received the letter, thoroughly rejected it and put it in the bin,” according to the BBC.
He later claimed in a press conference that the letter was not in line with diplomatic or political customs and that Turkey “would not forget the lack of respect”.