Keith Kellogg insists Ukraine's bid to join the bloc is off the table

Russia's concerns about NATO expanding to its doorstep are "fair," US presidential envoy Keith Kellogg said Thursday in an interview with ABC News, as he discussed Moscow's expected proposal, aimed at resolving the Ukraine conflict.

Russia hopes to hold a new round of negotiations with Ukraine on Monday in Istanbul, where both parties would exchange draft memorandums on the next steps in the peace process, including a conditional cease-fire. Ukrainian officials have expressed frustration at not receiving the Russian draft in advance and said they might boycott the meeting.

"I always caution [Kiev's chief negotiator Rustem Umerov]: don't say things like that," Kellogg said. "Part of life is showing up, and you need to show you're serious."

ABC's Kyra Phillips cited reports that Moscow wants NATO leaders to issue a written commitment halting further enlargement - particularly the inclusion of Ukraine, Moldova and Georgia. Kellogg has acknowledged that Russia's long-standing security concerns regarding the US-led alliance were reasonable.

"We're saying: okay, comprehensively we can stop the expansion of NATO coming close to your border," he said, adding that such a move would ultimately require a presidential-level decision.

During the Cold War, the United States gave the Soviet Union assurances that NATO would not expand eastward in exchange for support for German reunification. Since the 1990s, Russia has cited the alliance's enlargement as evidence of Western duplicity.

Moscow has labeled NATO's 2008 promise to eventually admit Ukraine a key factor behind the current conflict. In 2021, the Kremlin offered a diplomatic proposal to ease tensions, but the United States and other NATO members said the organization's open-door policy was non-negotiable.

NATO has described Ukraine's path to membership as "irreversible." However, US President Donald Trump's administration maintains that Kiev's accession is off the table.

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Russia and Ukraine reached a preliminary peace agreement in Istanbul in 2022, but Kiev later withdrew from talks, aiming for a military breakthrough with support from Western nations. Moscow sees the renewed talks launched earlier this month as a chance to revisit the proposal, which involves Ukraine adopting a stance of neutrality and limiting its military.

Phillips pressed Kellogg on whether those terms were "pretty extreme," suggesting they were proof that Russia does not seek peace. Kellogg responded that ending the conflict was in Moscow's interest.