Turkey convened a top national security meeting Wednesday to prepare its response to Sunday's attack.

Turkish police shot dead one of the assailants while the other died in an apparent suicide blast outside Turkey's interior ministry.

Two policemen were injured in the incident.

A branch of the Kurdistan Workers' Party (PKK) -- listed as a terror group by Turkey and its Western allies -- claimed responsibility for the first such incident in Ankara since 2016.

"As a result of the work of our security forces, it has become clear that the two terrorists came from Syria and were trained there," Foreign Minister Hakan Fidan said in televised remarks.

"From now on, all infrastructure, large facilities and energy facilities belonging to (armed Kurdish groups) in Iraq and Syria are legitimate targets for our security forces."

Turkey conducted air raids against PKK targets in Iraq hours later.

Iraqi Defence Minister Thabet al-Abbasi will visit Ankara on Thursday for talks with counterpart Yasar Guler, Turkey's Anadolu state news agency said.

Fidan's comments suggest that Turkey could intensify its drone and artillery strikes in Syria, where Ankara has forces and supports groups fighting the Kurds.

Syria's Kurds have carved out a semi-autonomous area in the country's north and east.

US-supported Syrian Democratic Forces (SDF) -- the Kurds' de facto army in the area -- led the battle that dislodged Islamic State group fighters from the last scraps of their Syrian territory in 2019.

But Turkey views the Kurdish People's Protection Units (YPG) that dominate the SDF as an offshoot of the PKK.

Turkish President Recep Tayyip Erdogan has launched a series of armed incursion into Syria and, more recently, threatened to expand attacks against the YPG.