Any potential peace deal for Ukraine would need to involve agreement on territory, with Russia currently occupying almost a fifth of Ukraine’s land.

The Trump administration "is making quite an energetic and sincere effort, in my opinion, to stop hostilities, to stop the crisis and to reach an agreement that is of interest to all those involved in this conflict," Putin said during a meeting of his top officials to prepare for the Alaska summit, according to a readout published by the Kremlin.

Whether the U.S.-Russia summit can lead to a deal to produce peace in Ukraine more than 3 1/2 years after Moscow’s invasion remains to be seen.