U.S. President Donald Trump has frozen military aid to Ukraine, just days after publicly confronting Ukrainian President Volodymyr Zelenskiy at the White House and accusing him of being insufficiently grateful for Washington's backing.

Ukraine has depended on a lifeline of arms from the United States since the day after Russian troops crossed the border in February 2022, when the Biden administration authorized $350 million worth of arms from the Defense Department’s stockpiles for Ukraine.

The U.S. move won’t have an immediate impact on the battlefield, where Kyiv’s forces are struggling to stem a relentless Russian offensive in eastern Ukraine. Ukrainian forces have slowed Russian advances along the roughly 1,000-kilometer (600-mile) front line, where Russia is slowly gaining ground at a huge human and material cost.