Turkey is doubling down on its animosity toward the Syrian Kurdish YPG militia, promising it is ready to conduct military operations against the YPG if provoked, and demanding the removal of a U.S. envoy for supporting the Kurds.

“Brett McGurk, the USA’s special envoy in the fight against Daesh, is definitely and clearly giving support to the PKK and YPG. It would be beneficial if this person is changed,” said Turkish Foreign Minister Mevlut Cavusoglu in a televised interview on Thursday.

“Daesh” is another name for the Islamic State. The Peoples’ Protection Units (YPG) is a Kurdish militia in Syria that is regarded as a battlefield ally by the United States. The Kurdistan Workers’ Party (PKK) is a violent Kurdish separatist organization in Turkey. The Turks insist the YPG and the PKK are closely linked. Turkey has bombed Kurdish positions in Syria and Iraq.

McGurk is the special U.S. presidential envoy to the international coalition against ISIS. According to Turkey’s pro-government Daily Sabah, Cavusoglu said one of the reasons President Donald Trump should consider replacing McGurk is that he is a holdover from the Obama administration.

“The new U.S. administration is more sincere than the previous one,” said the Turkish foreign minister, arguing that U.S. officials from the Obama administration could “pose threats to relations between the two countries” and “damage bilateral ties,” as Daily Sabah put it.

Al-Jazeera notes Turkish officials have criticized McGurk for what they saw as excessive sympathy to the Kurds in the past. Analysts told al-Jazeera that Cavusoglu’s demand for McGurk’s dismissal could be seen more as “an airing of Turkish frustration” than a serious demand from the Turkish government.

However, Reuters notes that Cavusoglu spoke only a few hours after Turkish President Recep Tayyip Erdogan, giving his first public address after returning from a trip to Washington, said Turkey would “exercise its rights under the rules of engagement” and attack the YPG if it felt the need to do so, without consulting the U.S. or NATO.

“We are facing a picture where terrorist organizations are constantly supported, strengthened and are confronting us. Turkey is not a country that will consent to such treatment,” Erdogan said, referring to the YPG. He also mentioned Turkey’s “Euphrates Shield” operation, a military incursion into Syria intended primarily to prevent the YPG from capturing strategic towns near the Turkish border.

Erdogan said he has informed the United States that Turkey will not participate in the liberation of the Syrian city of Raqqa from ISIS if the Kurds are involved. The Trump administration has signaled it will provide heavier arms to the Kurds so they can fight for Raqqa.