The outgoing president may urge Mr Trump to back Ukraine in its war with Russia, as Washington’s support for Kyiv hangs in the balance since Mr Trump's victory last week, with US secretary of state Antony Blinken vowing to bolster Kyiv as much as possible in the months prior to Mr Trump reassuming office.

Russia attacked the Ukrainian capital Kyiv with a sophisticated combination of missiles and drones for the first time in 73 days on Wednesday, authorities reported, as the Pentagon said most of the North Korean troops sent to help Moscow’s war effort are fighting to drive Ukraine’s army off Russian soil in the Kursk border region.