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.”
President Trump has faced intense criticism for the withdrawal of troops, which critics say gave Turkey the green light to launch the military attack.
Much of the criticism has come from within Mr Trump’s own party.
In a rare bipartisan rebuke, 129 members of the president’s Republican Party in the House of Representatives joined Democrats to formally denounce the move in a vote on Wednesday.
The joint resolution, which also called on President Erdogan to immediately cease military operations against Kurdish-led forces, was voted in by 354-60.