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 is open to holding a trilateral summit in Alaska with Russian President Vladimir Putin and Ukrainian President Volodymyr Zelenskiy, a White House official said on Saturday.

Earlier Thursday, when pushing back on Kremlin claims that a Trump-Putin summit had been set, a White House official had said Putin would also have to meet with Zelenskyy for the meeting to take place -- something the Kremlin has not been willing to commit to so far.