Though Trump's decision was welcomed by leaders in Kyiv, Ukrainians and their supporters abroad also raised concerns that the 50-day window may offer Russian President Vladimir Putin an opportunity to intensify his long-range strikes against Ukrainian cities and ongoing summer frontline offensive.

Ukraine's spy agency said a man and woman were suspected to be involved in the assassination that was caught on surveillance cameras.

Three Ukrainians were killed in the southeastern Dnipropetrovsk region, where Russia captured a first village this week after a months-long incursion. In the neighboring Zaporizhzhia region — the site of a nuclear plant — two civilians were killed in the attacks, Gov. Ivan Fedorov said.

Russia continued its nightly bombardment of Ukrainian cities overnight into Tuesday, after President Donald Trump said the U.S. would send military equipment to Kyiv.