Turkey’s foreign minister is set to travel to Russia on Monday to discuss the situation in Ukraine, following direct talks earlier this month in Istanbul between the two sides in conflict.

Ukraine’s President Volodymyr Zelensky raised the stakes ahead of a potential meeting with Vladimir Putin in Turkey by saying he wouldn’t hold talks with any Russian representative other than the president himself.

Sergey Lavrov expressed doubts about organizing peace talks at the Vatican, emphasizing the Orthodox roots of Russia and Ukraine. Another round of negotiations with Ukraine is planned, but details remain unknown.