"There are those who have sought to mediate between us and the terrorist organisation. What kind of prime minister, what kind of head of state are they? It's not possible to understand. When did you see a state sit at a table with a terrorist organisation?"
"Despite the fact that we've been saying this for months, we come across those who threaten us with such subjects like economic sanctions and arms embargoes. Those who think they will turn Turkey back from its path have been mistaken, are mistaken."
President Recep Tayyip Erdogan on Sunday slammed Western allies for standing by the Syrian Kurdish fighters and said Turkey would not negotiate with "a terrorist organisation".
Speaking in Istanbul, the president also rejected offers for mediation with the Syrian Kurdish militia as the Turkish military continues its offensive against them in northern Syria.
Without specifying which countries made a mediation offer, Erdogan asked: "What kind of prime minister, what kind of head of state are they?...When did you see a state sit at a table with a terrorist organisation?"
He also hit out at those countries calling for new sanctions and arms embargoes against Turkey, saying that "those who think they will turn Turkey back from its path have been mistaken, are mistaken".
NATO member Turkey views Syrian Kurdish militia as terrorists because of their links to an insurgency in the southeast of the country.
But those same Syrian Kurdish forces were a key US ally in the war against the Islamic State group.
Turkey has vowed to carve out a "safe zone" inside Syria along the border.