NATO has taken over air defenses in Poland from the US just days before the inauguration of President-elect Donald Trump, according to a NATO spokesman, with questions looming about the incoming administration’s approach to the alliance and to Ukraine.

Tensions between Ukraine and Hungary over the war with Russia and the expired gas transit deal continue to increase online.

Membership in NATO is the only credible long-term security guarantee Ukraine can receive against future Russian aggression, Finland's top diplomat said on Wednesday.

Ukraine's leader says partners sending ground troops would help "force Russia into peace," as America's European allies ponder Trump's next move.

"The whole [Trump] team is obsessed with strength and looking strong, so they’re recalibrating the Ukraine approach," one European official told the Financial Times.

Lago on Tuesday, president-elect Donald Trump marked the starting shot in what could be a make-or-break test for NATO over Ukraine, Greenland, and defence spending.

Ukraine's long-range drone strikes on airbases and ammunition depots inside Russia have reduced the glide-bomb threat.

Ukraine's Western allies will gather with President Volodymyr Zelensky at a US base in Germany on Thursday in their last such meeting before Donald Trump returns to the White House in less than two weeks.

NATO Secretary General Mark Rutte on Thursday urged continued military support for Ukraine after nearly three years of war, warning that reduced support could embolden countries like China, North Korea and Iran.

"We are supporting Ukraine's NATO membership further down the line and hopefully not in (the) too-distant future," Finland's Foreign Minister Elina Valtonen said on Jan. 8.