Turkish Prime Minister Ahmet Davutoglu on Tuesday criticised a visit to Russia by the main Kurdish opposition party leader, at a time when Ankara is at loggerheads with Moscow over the downing of a Russian warplane.

Selahattin Demirtas, leader of the opposition Democratic Peoples' Party (HDP), is set to meet Russian Foreign Minister Sergei Lavrov on Wednesday, the first high profile trip by any Turkish figure since the plane crisis.

"Why didn't they (the HDP) go two months ago? Why are they going at such a time?" Davutoglu asked his party's lawmakers at a meeting the parliament.

The November 24 shooting down of a Russian warplane on the Syrian border by Turkish forces has sparked an unprecedented crisis in Turkey's ties with Russia which accused Ankara of a planned provocation.

Davutoglu raised suspicions over the timing of the visit.

"Why are they going at such a time to a country with which we are having a crisis because of their violation of this nation's airspace?" Davutoglu asked.

"My friends -- they have taken it on as their moral duty to cooperate with whoever has a problem with Turkey instead of acting together with this nation."

Davutoglu also accused Russia of bombing civilians in Syria instead of focusing its operations on the Islamic State (IS) group.

"I am calling on Russia. Why are you bombing innocent civilians by saying 'we're fighting Daesh'," he said, using another name for IS.

Demirtas, seen as the only politician in Turkey who matches President Recep Tayyip Erdogan's charisma, unsuccessfully challenged the Turkish strongman in a 2014 presidential election.

Ankara is warily watching if Moscow will tighten ties with Kurdish factions in the wake of the plane crisis and in particular whether it allows Syrian Kurds to open an office in Moscow.