Donald Trump's election victory spells immediate doubt for Ukraine in its fight against Russia, with U.S. President Joe Biden's administration expected to sprint in its final days to ensure — insofar as possible — long-term U.S. support.

Trump, who won an overwhelming victory in Tuesday's election, has in the past voiced admiration for Russian President Vladimir Putin and scoffed at the $175 billion in U.S. assistance committed for Ukraine since Moscow's 2022 invasion.

The 78-year-old tycoon has repeatedly boasted that he can end the war in 24 hours, without explaining how.