The United States does not see a difference between Daesh's presence in Mosul and the PKK in Sinjar, and both groups must be defeated, Pentagon spokesman U.S. Air Force Colonel John Dorrian said on Tuesday.

Speaking in a press conference in Irbil with senior Kurdistan Regional Government (KRG) officials, Dorrian said the Mosul operation has made significant progress thanks to strong cooperation between Iraqi security forces and the U.S.-led international coalition.

When asked whether the U.S. had contacted the PKK for it to withdraw from Sinjar, Dorrian said the coalition is only in contact with the KRG and Iraq's central government, and that coordination with terror groups is out of the question.

Speaking about a possible assistance from the coalition to the KRG and the Iraqi government in an operation to cleanse the PKK from Sinjar, the colonel said the coalition would support all efforts against terrorists, without providing further details.

The predominantly-Yazidi town of Sinjar and its surrounding area were captured by Daesh terrorists during their blitz campaign in August 2014 that gave them control of large swathes of land in central and northwestern Iraq, in addition to the country's second largest city Mosul.

After the region was liberated from Daesh, the PKK took advantage of the situation and settled in Mount Sinjar. Turkey has repeatedly warned that it will not tolerate the PKK permanently basing themselves in Mount Sinjar, accusing the terror group of establishing a "second Mount Qandil," in reference to the group's current headquarters in northern Iraq near the border with Iran.