Ex-GOP candidate Chris Christie, speaking on NBC's "Meet the Press," called Trump unfit for presidency. Trump, at a rally, criticized NATO nations for "delinquent" payments, suggesting he'd let Russia act without interference.

The White House condemned Trump's comments as "appalling," and other Western officials joined in the criticism. NATO has experienced friction with members not meeting the 2% GDP defense spending benchmark, with only 11 of 31 members hitting the target.

Nikki Haley, Trump's opponent for the 2024 GOP nomination, opposed siding with Russia on CBS's "Face the Nation." Senator Lindsey Graham, typically a Trump ally, disagreed with Trump's way of expressing his NATO views, while Senator Thom Tillis attributed Trump's remarks to a lack of aide explanation. Senator Rand Paul called Trump's comments "stupid."

Amid Senate debates on aid to Ukraine and Israel, some Republicans like Senator Marco Rubio defended Trump, saying other presidents also pressured NATO members but Trump was frank. Trump aide Jason Miller deflected specific remarks and praised Trump's prior term.

Democratic Senator Peter Welch criticized Trump's behavior as belligerent and intentional.