A diplomatic scramble unfolded Saturday after President Donald Trump announced he would meet his Russian counterpart, Vladimir Putin, next week in Alaska, as European leaders rushed to understand the terms of the meeting and ensure Ukraine was not being left out of discussions about its future.

President Donald Trump and Russian President Vladimir Putin agreed to meet Friday in Alaska and might invite Ukrainian President Volodymyr Zelensky, too.

U.S. Ambassador to NATO Matthew Whitaker said “it’s possible” that Ukrainian President Volodymyr Zelensky attends the upcoming meeting between President Trump and Russian President Vladimir Putin in Alaska.