Former CIA Director David Petraeus told ABC News' "This Week" he's doubtful that Russian President Vladimir Putin and Ukrainian President Volodymyr Zelenskyy will meet.

Speaking on NBC's "Meet the Press with Kristen Welker", Vance said Russian President Vladimir Putin has made several concessions, including that Ukraine will receive security guarantees protecting against future Russian aggression.

Russia's leader said he was "confident that the leadership qualities" of Trump are a "good guarantee" of future agreements between global superpowers.

President Vladimir Putin said on Friday that there was "light at the end of the tunnel" in Russia-U.S. relations and that the two countries were discussing joint projects in the Arctic and Alaska. The Russian president,

President Donald Trump started the week declaring a diplomatic breakthrough in his bid to get Russia and Ukraine closer to making peace, announcing he had begun arranging for direct talks between Russia’s Vladimir Putin and Ukraine’s Volodymyr Zelenskyy.

The president, who had said a deal to end the war could be reached soon, expressed frustration over lack of progress and signaled he would pause his efforts.