NATO has offered political support for Turkey's campaign against fighters in Syria and Iraq at a rare meeting in Brussels, as Ankara said the alliance may have a "duty" to become more involved.
The extraordinary meeting at the NATO headquarters on Tuesday is the fifth in the organisation's 66-year history. It came just days after Ankara launched air strikes targeting ISIL in Syria and Kurdish fighters in Iraq.
The session was requested by Turkey under Article 4 of the treaty that founded the US-led alliance, which empowers its 28 member states to seek such consultations when they consider their "territorial integrity, political independence or security" to be in jeopardy.
"We stand in strong solidarity with our ally Turkey," NATO Secretary-General Jens Stoltenberg told alliance ambassadors at the start of a meeting he called right and timely "to address instability on Turkey's doorstep and on NATO's border".
In the run-up, both NATO and Turkey played down any idea that the military alliance might provide air or ground support for Turkey's dramatic change in strategy, but President Recep Tayyip Erdogan suggested otherwise.
Turkey had "come under attack", he said of a bombing blamed on ISIL that killed 32 mostly young students last week in the Turkish town of Suruc on the border with Syria.
"If a NATO member country comes under attack, NATO would support it in every way," Erdogan said.
"At the moment, Turkey has come under attack and is exercising its right to defend itself and will exercise this right until the end ... but what we're saying is that there could be a duty for NATO, and we ask NATO to be prepared for this."
After months of reluctance, Turkish warplanes last week started striking targets in Syria after the country entered a long-awaited agreement which allows the US to launch its own strikes from the strategically located Incirlik airbase.
The US and Turkey on Monday were also finalising plans for a military campaign to push the ISIL group out of a strip of Syrian territory along the Turkish border.
Turkey has also been bombarding positions belonging to the Kurdistan Workers' Party (PKK) in northern Iraq.
Before a truce with Ankara in 2013, the PKK fought Turkey for autonomy for Kurds in a conflict that has claimed tens of thousands of lives since 1984. Turkey fears they could revive an insurgency against it in pursuit of an independent state.
While Turkey on Monday said that it will not target areas in Syria under the control of PKK-affiliated People's Protection Units (YPG), some reports had emerged that Turkish tanks shelled Kurdish-held villages on Sunday night.
The Syrian Kurds are among the most effective ground forces battling the ISIL group and have been aided by US-led air strikes.