Turkish President Recep Tayyip Erdogan put the letter from US President Donald Trump "in the trash," the BBC reported.
In a letter of 9 October and sent after US troops were withdrawn from Syria, Mr Trump told Mr Erdogan: "Don't be a healthy person. Don't be a fool!"
Turkish presidential sources told BBC Turkish that the letter was "completely rejected" by Mr Erdogan.
On the day the letter was received, Turkey launched a cross-border offensive against Kurdish-led forces.
"Let's make a good deal! You don't want to be responsible for killing thousands, and I don't want to be responsible for destroying the Turkish economy ̵
"History will look at you favorably if you do it right and humane. It will look at you forever as the devil if good things don't happen."
In response, Turkish presidential sources say: "President Erdogan received the letter, rejected it completely and put it in the trash."
It is difficult to imagine a language like it in many letters between presidents.
The mix of threats and hiding of Donald Trump infuriated Turkish President Recep Erdogan. His staff told the BBC that he had thrown the letter in the bin and started the Syrian operation the same day. This could be evidence that there is no green light on the log.
But since President Obama partnered with SDF Syrian Kurds against IS jihadists, it has been clear that the agreement will lead to problems with the Turks. This is because the SDF is very close to the Turkish Kurds of the PKK. Turkey says they are two halves of the same terrorist group.
Presidents Erdogan and Trump discussed hostilities last December. Diplomatic sources here in Ankara suggest that Turkey's broader strategic goal was to rip off Kurds and Americans.
This has, in any case, happened.
The diplomatic debate surrounding events in and around Syria is the backdrop of President Erdogan's meeting in Ankara with a US delegation led by Vice President Mike Pence and Secretary of State Mike Pompeo. It is difficult to find common ground between the two countries.
How did others respond to the crisis?
President Trump has faced intense criticism of the withdrawal of troops, which critics say has given Turkey the green light to launch a military attack.
Much of the criticism comes from within Mr Trump's own party.
In a rare two-party reprimand, 129 members of the Republican Presidential Party in the House of Representatives joined the Democrats to formally denounce the move Wednesday.
The joint resolution, which also called on President Erdogan to immediately cease military operations against Kurdish-led forces, was voted 354-60.
Cabinet Chairman Nancy Pelosi also had an apparently explosive meeting with President Trump on the issue, which led to her and Senate Minority Leader Charles Schumer leaving the House.
Republican leaders said Ms. Pelosi's behavior was "invincible" and was criticized for "breaking out".
Ms. Pelosi and Mr. Trump also accused the other of "collapse", with the president later tweeting a picture of their confrontation.
But the image was praised by Democrats, who said it was "emblematic" and showed Mrs. Pelosi's "best moment". Ms. Pelosi also took the photo of her top image on Twitter.
What did Trump say?
Earlier Wednesday, President Trump said the United States should not interfere in Turkey's military operation in Syria because "it is not our border" and called the former US allies the Kurds "without angels."
"They have a border problem," he told reporters at the White House. "This is not our border. We should not lose our lives."
The president also said he believed the situation at the border between Turkey and Syria was "strategically brilliant" for the US.
"Our soldiers are from there. Our soldiers are completely safe. They have to deal. Maybe they can do that."
"We are watching and negotiating and trying to get Turkey to do the right thing because we want to stop. wars regardless. "
The Kurds, he added, "They fought with us. We made a lot of money for them to fight us. That's good. They did well when they fought us. They didn't do so well when they didn't fight with us. "
What is the context?
Kurdish-led forces have been a critical ally of the United States in the fight against the Islamic State (IS) group i n Syria.
However, there are concerns that this destabilization may lead to the resurgence of jihadists.
Turkish troops and allied Syrian rebels launched an offensive in northern Syria last week against members of a Syrian Kurdish militia called People's Protection of the People (YPG
The goal, they said, was to push the YPG back from the border and create a "safe area" where up to two million Syrian refugees can be resettled.
On Wednesday, Mr Trump also said a rebel group fighting for Kurdish autonomy in Turkey – called the Kurdistan Workers' Party (PKK) – "probably is worse than terror and more oh terrorist threat in many ways from IS.
The PKK has already been designated as a foreign terrorist organization by the US and a Specifically designated global terrorist entity.
Turkey views the YPG as an extension of the PKK – a claim the US rejects.
The YPG has been a large part of an alliance of Kurdish and Arab militias called the Syrian Democratic Forces (SDF), which has helped drive the IS out of a quarter of Syria over the past four years.
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