A day after exchanging some of the most intense air attacks of the war, Russia and Ukraine were set to meet in Istanbul on Monday for peace talks, discussions that will be complicated by their entrenched positions and the situation on the battlefield.

Russia and Ukraine are expected to formally exchange their respective conditions for a deal in the second round of negotiations since the two sides resumed direct dialogue two weeks ago.

Expectations are low. Moscow and Kyiv are talking under pressure from President Trump, who has alternatively cajoled and chided both countries’ leaders. But Russia and Ukraine have been holding firm, with neither expected to present conditions in the discussion that are acceptable to the other side.

As negotiations sputter, the attacks on the battlefield have intensified. The Russian army appears to be launching a new offensive, advancing at the fastest pace since last fall and opening a new front in the northern Sumy region. It has also bombarded Ukrainian cities with some of the biggest drone and missile attacks of the years, including a barrage of 500 drones and decoys on Sunday.

Ukraine, for its part, has adapted and evolved in the face of a much larger military with deeper resources. Ukrainian drones, in an ambitious, coordinated attack, struck air bases deep inside Russia this weekend.

In recent days, President Volodymyr Zelensky of Ukraine dampened expectations for the discussions, confirming only on Sunday afternoon that a Ukrainian delegation would travel to Istanbul. “Nevertheless, we will try to achieve at least some progress on the path to peace,” he said a few hours later.