ERBIL, Kurdistan Region of Iraq - NATO Secretary General Mark Rutte said Thursday that he was "cautiously optimistic" about progress towards peace in Ukraine, as Kyiv and Moscow are set to hold the first direct talks in three years in Istanbul.

Speaking at a NATO meeting in Turkey, the former Dutch prime minister turned head of the defense alliance said, "I'm still cautiously optimistic that if also the Russians are willing to play ball, and not only the Ukrainians are doing this... that you could get to some breakthroughs over the next couple of weeks.”

Russian President Vladimir Putin will not attend Thursday’s talks despite a challenge from his Ukrainian counterpart, Volodymyr Zelensky, to meet him face-to-face, with Rutte noting that Moscow had instead chosen to send a “lower-level delegation” to Turkey.

Zelensky is set to meet his Turkish counterpart, Recep Tayyip Erdogan, in Ankara on Thursday, though it remains unclear if he will show up to talks given that Putin has spurned his challenge.

US President Donald Trump will also not be in attendance, instead closing out his three-day Gulf trip with a brief stopover in the UAE. Trump had previously toyed with the notion of making the journey to Istanbul should Putin be willing to meet him, saying on Wednesday, “I know he would like me to be there, and that’s a possibility. If we could end the war, I’d be thinking about that.”

Russia is expected to push for recognition of sovereignty over the Ukrainian territories it has occupied in any peace accord, while Kyiv demands a complete ceasefire, with Zelensky having also repeatedly highlighted the salience of “security guarantees” in securing any lasting deal.