The future of U.S. aid for Ukraine hangs in the balance after a last-gasp deal to avoid a government shutdown, despite President Joe Biden's attempts to reassure Kyiv it will get what it needs to fight Russia.

Barely a week after Ukrainian President Volodymyr Zelenskyy was in Washington appealing for more funds, the compromise struck in Congress late Sunday dropped new funding for Ukraine amid opposition from hard-line Republicans.

Biden and his Democratic Party say America has a duty to help Ukraine stand up to Russian President Vladimir Putin's brutal invasion, warning that a failure to do so could embolden other autocrats in the future.