US President Donald Trump has gone all in with his effort to strongarm Kyiv into peace negotiations with Russia, suspending US military aid to Ukraine with immediate effect.

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.

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.