The Kremlin declined to say on Tuesday whether President Vladimir V. Putin of Russia would attend talks with Ukraine’s leader this week, after President Trump floated the possibility of attending himself to push for a peace deal.

Over the weekend, Mr. Putin called for direct talks with Ukraine, while ignoring demands by Kyiv and its allies to agree to an immediate cease-fire by Monday or face further sanctions. Mr. Trump then implored Ukraine to take the meeting, and President Volodymyr Zelensky said he would travel to Turkey to attend personally — challenging Mr. Putin to do the same.

But when asked on Tuesday who would lead Russia’s delegation for the talks, the Kremlin spokesman would not comment.