European leaders are planning a meeting with President Trump before a U.S.-Russia summit, stressing that a long-term security guarantee for Ukraine is fundamental.

European leaders will hold a videoconference on Wednesday ahead of one with U.S. President Donald Trump to coordinate negotiations to end the war in Ukraine with Russia's President Vladimir Putin, a German government spokesperson said on Monday.

The Kremlin leader believes time is on his side as the exhausted and outgunned Ukrainian forces are struggling to stem Russian advances.