President Recep Tayyip Erdoğan will represent Turkey at a North Atlantic Treaty Organization (NATO) summit which will be held in Poland on July 8-9.

The summit, which will be the last attended by U.S. President Barack Obama, will mainly focus on strengthening the organization's Eastern Europe borders, Russia's activities in the region, the crises in Syria and Iraq, as well as DAESH's activities.

Apart from the official agenda of the summit, President Erdoğan is expected to raise Ankara's concerns at bilateral meetings regarding the Syrian crisis, which has led to instability in the region and created a huge wave of refugees.

Erdoğan is also expected to express his frustration over the Syrian PKK-affiliate, the Democratic Union Party's (PYD) armed wing, the People's Protection Units (YPG).

Ties between Washington and Ankara have recently soured over the PYD and the YPG, with the U.S. insisting that the YPG is an effective partner in the fight against DAESH.

Ankara has reiterated that no distinction can be made between good or bad terrorist organizations, and asserts that both the PYD and the YPG are affiliated with the PKK, which has been designated as a terrorist organization by the U.S., the EU and NATO.

Turkey's plan for a safe zone along the Turkish-Syrian border will be reiterated at the bilateral meetings, according to sources in Ankara. Other topics to be discussed at the summit will reportedly be cyber-security and security of natural energy resources.

U.S. defense chief: NATO to take part in anti-DAESH battleNATO will take "a more direct role" in the fight against DAESH, U.S. Secretary of Defense Ash Carter said on Monday. "First by contributing AWACS [Airborne Warning and Control System] and conducting training and defense capacity building for Iraq inside Iraq rather than in Jordan," Carter said at an annual conference of the Center for New American Security think tank. "Hopefully that will be the start of more to come."

Carter did not provide further details about the alliance's role in the fight against DAESH, but the subject was apparently discussed at a NATO ministerial meeting in Brussels earlier this month, and will be discussed next month at the NATO summit in Warsaw, Poland.

The top defense official said the alliance will complement the EU's efforts to deal with migrant and refugee crisis in the Mediterranean Sea and the Aegean Sea. Carter added that as a part of that effort, the U.S. is sending a rescue and salvage ship with capabilities to give assistance to disabled ships, provide towing, diving, firefighting and heavy lift abilities.More than 206,000 migrants or refugees have crossed into Greece and Italy since the beginning of this year, according to the International Organization for Migration (IOM).

In the past four years, 1.4 million refugees have crossed the Mediterranean, according to IOM data, and more than 8,100 refugees died during that same period.