"A Turkish army drone struck a PKK vehicle, killing an official and two fighters" of the group -- considered a terrorist organisation by Turkey and Western countries -- in the Sidakan district, the Kurdish counter-terrorism services said.

It came as Turkish Foreign Minister Hakan Fidan was visiting the Iraqi Kurdish regional capital Arbil after he began on Tuesday his first official trip to Iraq.

Fidan is due to meet the Kurdish president and prime minister amid calls by Ankara for Baghdad to label the PKK a terrorist organisation.

Iraq's autonomous Kurdistan region has long been a target of Turkish air and ground operations against the PKK, which has waged a decades-long insurgency against Ankara.

The Turkish military rarely comments on individual strikes in northern Iraq.

Both the Kurdish authorities in Arbil and the federal government in Baghdad have long been accused of not doing enough to stop Turkey's frequent resort to military action on Iraqi soil in its nearly four-decade struggle against the PKK.

Statements condemning the violation of Iraqi sovereignty are periodically issued, particularly when there are civilian casualties.

But critics say both Arbil and Baghdad are more concerned with protecting trade and investment ties with Ankara.

On July 25, the office of Prime Minister Mohamed Shia al-Sudani announced a forthcoming visit to Iraq by Turkish President Recep Tayyip Erdogan, but a date has yet to be set.