After months of unsuccessful diplomatic efforts to end the Ukraine war, President Donald Trump faces a pivotal moment as he meets face-to-face with Vladimir Putin to prod the Russian president on a peace deal.

Putin invaded Ukraine in 2022 and has been reluctant to halt the bloody conflict, frustrating Trump, who has lashed out and threatened economic penalties. The Aug. 15 summit is a test of whether Trump can make progress on a deal that is acceptable to both Ukraine and Russia.

The two leaders are meeting at a U.S. military base in Alaska. Not invited: Ukrainian President Volodymyr Zelenskyy, who spoke with Trump twice this week and has rejected the idea of territorial concessions to end the war.