The Republican front-runner said that, as president, he warned NATO allies that he "would encourage" Russia "to do whatever the hell they want" to countries that don't meet their spending commitments.
Voters in Finland were electing a new president Sunday at an unprecedented time for the Nordic nation that is now a NATO member with its eastern border with Russia closed.
Turkish legislators endorsed Sweden's membership in NATO, lifting a major hurdle on the previously nonaligned country's entry into the military alliance.
The NATO and EU member borders Belarus, the Russian territory of Kaliningrad and Ukraine — plus a strip of land connecting it to Lithuania. It is an unstable and volatile mix of frontiers.
NATO's expansion is the exact opposite of what Russia wanted, says Secretary-General Jens Stoltenberg. He spoke to NPR about its NATO's newest members, and when Ukraine might join them.
Ukrainian President Volodymyr Zelenskyy left the NATO summit satisfied with offers of long-term security aid from the United States and other G-7 countries, according to President Biden.
The war in Ukraine will be top of mind when leaders from North America and Europe meet in Lithuania. So will the makeup of the alliance itself, as Ukraine continues pushing for membership.
President Biden is in Europe this week. He first talked climate change with King Charles. Then he's meeting NATO leaders in Vilnius, Lithuania to talk about the war in Ukraine.
Erdogan's support for Ukraine comes as Turkey has been holding off giving final approval to Sweden joining NATO, saying Stockholm is not effectively cracking down on groups Ankara view as threats.