President Recep Tayyip Erdoğan held a meeting with U.S. Vice President Mike Pence at the Presidential Complex in the capital Ankara, as Turkey is carrying out a crossborder operation in northeastern Syria.

The meeting started at 3:40 p.m. (1240GMT).

The two discussed Turkey's ongoing anti-terror operation in northern Syria.

Pence arrived in Ankara earlier on Thursday, leading a delegation including Secretary of State Mike Pompeo.

U.S. President Donald Trump had earlier invited Erdoğan to the White House on November 13. The Turkish leader has said he will only decide on visiting Washington after the U.S. delegation talks.

Pence is scheduled to leave Ankara later Thursday.

Russia's special envoy to Syria, Alexander Lavrentyev, was also at the presidential palace in Ankara on Thursday and met Erdoğan's spokesman, Ibrahim Kalın, the presidency said.

Erdoğan will meet Russian President Vladimir Putin on October 22 in the Black Sea city of Sochi.

Turkey launched Operation Peace Spring, the third in a series of cross-border anti-terror operations in northern Syria targeting terrorists affiliated with Daesh and the PKK's Syrian offshoot the People's Protection Units (YPG), on October 9 at 4 p.m.

The operation, conducted in line with the country's right to self-defense borne out of international law and U.N. Security Council resolutions, aims to establish a terror-free safe zone for Syrians return in the area east of the Euphrates River controlled by the U.S.-backed Syrian Democratic Forces (SDF), which is dominated by YPG terrorists.

The PKK — listed as a terrorist organization by Turkey, the U.S. and the European Union — has waged a terror campaign against Turkey for more than 30 years, resulting in the deaths of nearly 40,000 people, including women, children and infants.