Polling stations, which opened at 7 a.m., are to close at 8 p.m., after which initial exit polls will be announced while preliminary results are expected on Monday.
Efforts by the Trump administration since early last year to end the war have made no significant progress, and there was no suggestion of an imminent breakthrough.
The change has come at a time of renewed tension between Kyiv and Washington, with US President Donald Trump seeking to bring down global fuel prices by buying Russian diesel and pressuring both sides ...