Trump affirms US 'will always be there for NATO,' while expressing doubts about alliance

The president claimed responsibility for strengthening NATO, saying that his work has served as the main deterrence for China and Russia.

"Without my involvement, Russia would have all of Ukraine right now. Remember, also, I single-handedly ended 8 wars, and Norway, a NATO member, foolishly chose not to give me the Noble Peace Prize. But that doesn't matter! What does matter is that I saved millions of lives. Russia and China have zero fear of NATO without the United States, and I doubt NATO would be there for us if we really needed them. Everyone is lucky that I rebuilt our military in my first term, and continue to do so," Trump said.

The negotiations aimed at ending the Russia-Ukraine war remain active but have yet to reach the end stage of the deal-making process. On Tuesday, the U.K. and France signed a declaration pledging troops for Ukraine under a future peace deal and with security guarantees supported by the U.S. and allied partners.

A key U.S. role is outlined in plans for a continuous, U.S.-led ceasefire monitoring and verification mechanism, with contributions from partners. The U.S. would participate in a special commission to manage ceasefire breaches, attribute responsibility and determine solutions.

Meanwhile, NATO allies have expressed concern as Trump appeared to renew his push for the U.S. to take Greenland. The president told reporters on Air Force One that the U.S. needed the self-governing Danish territory for "national security" reasons.

"We need Greenland from the standpoint of national security, and Denmark is not going to be able to do it," Trump said.

Danish Prime Minister Mette Frederiksen on Monday warned that Trump's threats to annex Greenland could mean the end of NATO. Frederiksen told Danish broadcaster TV2 in an interview that Trump's threats about Greenland should be taken seriously. Since then, several world leaders, including those hailing from NATO-allied countries, have expressed concern about Trump's remarks on Greenland.

Fox News Digital's Emma Bussey and Ashley Carnahan contributed to this report.