By Erin Banco, Gram Slattery and Humeyra Pamuk WASHINGTON/RIYADH/ANTALYA, Turkey (Reuters) - U.S. President Donald Trump's senior envoys Steve Witkoff and Keith Kellogg will travel to Istanbul for potential talks on Thursday on how to end the war in Ukraine,

Ukrainian officials say Russia launched more than 100 drones, rejecting calls for a ceasefire as Zelenskyy says he'll "be waiting for Putin" to join him for direct talks in Turkey.

Both Moscow and Kyiv each accused the other of violating a truce Ukraine had never agreed to — even as it prompted Ukraine, with backing from European leaders (France, Germany, the United Kingdom and Poland) and the United States (it seems), to demand an extended 30-day ceasefire from the Kremlin.

President Trump on Sunday urged Ukrainian leaders to agree to meet with Russian President Vladimir Putin in Turkey later this week to negotiate an end to the three-year conflict. “President

The Kremlin brushed off the threat of further sanctions, saying that “the language of ultimatums is unacceptable.”

Moscow has hit back at Europe's 30-day ceasefire ultimatum as “unacceptable” and “unsuitable” following Western threats of sanctions.Kremlin spokesperson Dmitry Peskov said it was wrong to “use such language with Russia” as Europe’s deadline for Russia to agree to a truce with Ukraine got closer.