In addition to threatening Kurdish forces in Syria and Iraq, President Recep Tayyip Erdogan in a speech on Thursday reiterated Ankara’s willingness to send troops to Islamic State’s (IS, formerly ISIS/ISIL) Syrian stronghold Raqqa after dealing with al-Bab. Erdogan also said he had informed the US of the plans on Wednesday.

Turkish Defense Minister Fikri Isik told state broadcaster TRT on Thursday that Ankara does not want Kurdish forces to take part in a future offensive on Raqqa, and has asked the US not to call them in. The US military had earlier said Kurdish YPG militias would be part of the offensive against IS in Syria.

Turkey launched a ground incursion into Syria in August, attacking both IS and Kurdish militias. The force includes both Turkish regular troops and Turkish-backed Syrian militias fighting as the Free Syrian Army (FSA). The Turkish Air Force supports the offensive.

Kurdish militias have been a key ally of the US-led coalition fighting Islamic State both in Syria and Iraq. Iraqi Kurds are taking part in the ongoing offensive against Mosul, another stronghold of the terrorist organization. In Syria, coalition airstrikes helped a mixed Kurdish-Arab force dominated by the YPG to take Manbij from IS in August.

The US support for the Kurdish fighters has angered Ankara, which considers them terrorists and a major security threat to Turkey. The Kurdistan Workers’ Party (PKK) in Turkey waged a decades-long guerrilla war against the Turkish government. Ankara says Kurds in neighboring Syria and Iraq are helping the PKK in the hostilities and regularly attacks Kurdish positions in both countries.

The Mosul operation in Iraq highlighted the disarray in the coalition, with Turkey forcing its way into taking part in the campaign despite objections from the Kurds and the Iraqi government. It also insisted that Shiite militias, which helped the regular Iraqi Army fight IS, were not part of the offensive.

On Wednesday, Turkish Foreign Minister Mevlut Cavusoglu threatened that Turkey will use its ground forces in Iraq to attack the Kurds if it felt threatened. In his Thursday speech, President Erdogan said Turkey would not allow the Kurdish militias holding the region of Sinjar west of Mosul to turn it into a new base for the PKK.

Launching an offensive in Raqqa is reportedly an option that the administration of President Barack Obama may take before he leaves office in January. Providing more weapons to the Kurds is considered a possible element for such an operation, but Turkish actions, which have already disrupted the White House’s timetable for Raqqa, have put the plan into question, the New York Times reported last week.