RIGHT SPEAK: Turkey is coming under increased Pressure to Join the Campaign against the Islamic State

Turkey is showing signs of shifting to a more active role in the campaign against extremist group Islamic State as the government faces pressure from impatient U.S. and Arab officials.

President Barack Obama called Turkish President Recep Tayyip Erdogan from Air Force One on Thursday and the two leaders agreed to consult more closely on the Islamic State threat. Vice President Joe Biden met Mr. Erdogan in New York on Thursday.

A man carries mattresses as Syrian refugees fleeing

fighting with Islamic State militants cross the border

near Suruc, Turkey. Yasin Akgul/Zuma Press

Those contacts followed other meetings this week at the United Nations General Assembly where U.S. and Arab officials, concerned that Turkey is emerging as the weak link in the campaign, pressed it to formally join the coalition.

A North Atlantic Treaty Organization member that is home to a large American air base, Turkey has been conspicuously absent as a U.S.-led military coalition including Gulf Arab countries conducted a series of airstrikes on the radical Sunni group in neighboring Syria this week. At minimum, U.S. officials say, Mr. Obama wants Mr. Erdogan to do more to stop the flow of foreign fighters in and out of Turkey.

"We have made a clear declaration of political will against the Islamic State," a senior Turkish official said on Thursday. "We are discussing political and military cooperation, but the question is how we commit."

The official added that Turkey would decide the scope of cooperation based on its own security concerns and not based on international pressure.

"We will make this decision in Ankara," he said.

Turkey's rhetoric has shifted since it secured the release Saturday of 46 Turkish hostages held by Islamic State and under pressure from the sustained lobbying effort by Western leaders.

Stung by criticism for abstaining from the U.S.-led coalition, Mr. Erdogan flagged the shift when he was in New York for the General Assembly. He said Turkey would provide the operation with the necessary support, which could be military or diplomatic.