ANKARA, Turkey — The United States risks major damage to its relationship with NATO ally Turkey if the U.S. includes Kurdish forces in the fight to retake Raqqa, the Islamic State group’s de facto capital, Turkish Prime Minister Binali Yildirim said Thursday. Turkey and the U.S. are locked in a heated dispute about U.S. plans to liberate Raqqa, with Turkey insisting its own military and allied forces in Syria should mount the fight and that U.S.-backed Syrian Kurds should be excluded. Though the U.S. has been hoping to include both Turkey and the battle-hardened Kurdish forces, Yildirim insisted Turkey wouldn’t be part of any operation including the Syrian Kurdish force known as the YPG, considered by Ankara to be terrorists who threaten Turkey’s security. Today's WorldView What's most important from where the world meets Washington Please provide a valid email address. “If the U.S. were to prefer terrorist organizations over Turkey in the fight against IS, that would be their own decision, but that wouldn’t be something we would consent” to, Yildirim told The Associated Press. The prime minister also took issue with President Donald Trump’s use of the phrase “radical Islamic terrorism” and said “we would be actually happy if our friends were to be a bit more cautious about this issue.” In an earlier exchange with visiting foreign journalists, Yildirim said ties between the two countries would be significantly undermined, though he declined to name any specific steps Turkey — a member of the U.S.-led coalition fighting IS — might take in response. In the past, Turkey has hinted it could cut off access to Incirlik air base, home to coalition warplanes. Though no decision has been formally announced, the U.S. has been sending signals that it is inclined to rely on the Kurdish forces, who have proven the most effective local force at battling IS. U.S. officials have said that Turkey, which has troops in Syria and is aiding other Syrian opposition fighters, has thus far failed to show that it has a force sufficiently large and capable to liberate Raqqa, the largest remaining IS stronghold. Yildirim insisted Turkey has proven its mettle, pointing to victories by its Operation Euphrates Shield in liberating northern Syrian towns of Jarabulus and al-Bab. Yet in al-Bab, in particular, Turkish troops and allied Syrian fighters suffered heavy casualties in a grueling three-month fight to liberate the city from IS. “They know what our capabilities are,” Yildirim said. “We’ve exchanged military info, and diplomatically speaking this message was also passed along.” Turkey views the main Kurdish force — the People’s Protection Units, or YPG — to be terrorists because of their ties to Turkey’s outlawed Kurdistan Workers’ Party, or PKK, which the U.S. also considers to be a terrorist group. But the top American commander for the fight against IS has said he’s seen “zero evidence” the YPG has posed a recent threat to Turkey. Yildirim said Turkey is still awaiting a U.S. decision on Raqqa, and there are signs such a decision could come soon. The top U.S., Russian and Turkish generals met this week to discuss Syria, and the U.S. disclosed Wednesday it has deployed a couple hundred Marines into Syria with heavy artillery in preparation for the Raqqa operation. Frustrated by former President Barack Obama’s approach in the final years of his term, Turkey has been cautious in its approach to the new Trump administration while voicing optimism that relations with the U.S. will improve. Yildirim declined to criticize Trump’s revised order temporarily banning immigration from six majority-Muslim nations — Turkey is not one of them — but did suggest Trump should cease linking Islam to terrorism in his public comments. He suggested that when Turkish President Recep Tayyip Erdogan has his first meeting with Trump, he would raise objections to Trump’s use of phrases like “radical Islamic terrorism.” “This is simply divisive language,” Yildirim said. “Because if you mention one particular religion in the same sentence as terrorism, then the followers of that faith — which in this case is 2 billion people — they will be disturbed, and this is not the right thing to do.”