Turkish President Recep Tayyip Erdogan put US President Donald Trump's letter “in the bin”, the BBC has been told.
In the letter dated 9 October, and sent after US troops were pulled out of Syria, Mr Trump told Mr Erdogan: “Don't be a tough guy. Don't be a fool!”
Turkish presidential sources told the BBC that the letter was “thoroughly rejected” by Mr Erdogan.
On the day the letter was received, Turkey launched a cross-border offensive against Kurdish-led forces.
“Let's work out a good deal! 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,” Mr Trump said in the letter.
“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.”
In response, Turkish presidential sources said: “President Erdogan received the letter, thoroughly rejected it and put it in the bin.”
