The West must remain united as it enters a decisive moment for Ukraine's future and European security, Polish Prime Minister Donald Tusk said on Saturday after a summit between President Donald Trump and Russian President Vladimir Putin in Alaska.

"The game for Ukraine's future, the security of Poland and all of Europe has entered a decisive phase," Tusk wrote on X.

"Today, it is even clearer that Russia respects only the strong, and Putin has once again proven to be a cunning and ruthless player. Therefore, maintaining the unity of the entire West is so important."