Putin arrives in Ankara to meet with President Erdogan

Russian Federation has neither supported nor condemned the referendum, which was held on September 25, although the Kremlin issued a statement after the vote and said it was in favor of a united Iraq.

Putin plans to compare notes with Turkey's President Recep Tayyip Erdogan on issues including peacekeeping in Syria, the Kremlin spokesman said.

Erdogan's office said in a September 27 statement that the two are expected to discuss bilateral relations "as well as regional and worldwide matters, particularly Syria and Iraq".

Moscow sides with Syrian President Bashar Assad while Turkey has supported his foes since the start of the Syrian civil war six years ago.

Turkey sent more tanks, artillery units and armored carriers to the border region with Syria following the agreement with Russian Federation and Iran on Idlib, which came out of talks on how to end Syria's six-year civil war.

Putin was welcomed by Erdogan on Thursday afternoon with an official ceremony at the presidential compound. "The necessary conditions have been created for putting an end to the fratricidal war in Syria, completely destroying terrorists and allowing Syrians to return to peaceful life".

The Syria deal helped warm up ties and restore bilateral trade and the flow of Russian tourists to Turkey, halted in the wake of the 2015 plane incident.

Commenting on the Kurdish Regional Government (KRG) referendum in northern Iraq, Turkey's president Erdogan reiterated that it had "no legitimacy" in terms of Iraqi constitution and global law.

The Kremlin has yet to explicitly condemn the referendum, stressing instead the importance of maintaining Iraq's territorial integrity.

The situation in Syria and de-escalation zones are expected to be the main issues on the table.

The S-400 surface-to-air missiles deal that Moscow and Ankara signed this month is seen as a snub to Turkey's Western NATO allies.