Special U.S. envoy Steve Witkoff said Sunday that Russian leader Vladimir Putin agreed at his summit with President Donald Trump to allow the U.S. and European allies to offer Ukraine a security guarantee resembling NATO's collective defense mandate as part of an eventual deal to end the 3 1/2-year war.

Former National Security Advisor Jake Sullivan disputes Secretary of State Marco Rubio's characterization that continuing negotiations with Russian President Putin are a step toward ending the war in Ukraine.

Secretary of State Marco Rubio said Sunday that President Donald Trump's position on the war in Ukraine hasn't changed after Friday's summit with Russian President Vladimir Putin in Alaska and that Ukraine's involvement is essential for a peace deal.

President Trump offered security guarantees to deter future Russian aggression. But the offer was vague, prompting Kyiv to seek clarity.

In the letter addressed to Putin, the first lady said he could "singlehandedly restore" the "melodic laughter" of children who have been caught in the conflict.

One key party not be in attendance Friday at Joint Base Elmendorf-Richardson in Anchorage, Alaska, was Ukrainian President Volodymyr Zelenskyy. Trump said after his meeting with the Russian president that he would call Zelenskyy and update him on the talks.

President Donald Trump said on social media Saturday that a deal better than “a mere Ceasefire” is in the works with Vladimir Putin, hours after Trump’s high-stakes summit with the Russian leader in Alaska failed to produce an agreement to halt Russia’s invasion of Ukraine.

President Trump and Russian President Vladimir Putin are scheduled to meet Friday at Joint Base Elmendorf-Richardson in Anchorage, Alaska, to discuss the conflict between Russia and Ukraine.