What is NATO’s Article 5, the collective defense guideline which Trump says will be used to protect Ukraine and can US attack Russia if war continues?

US President Donald Trump said on Sunday (August 17, 2025) that Ukraine will not join the NATO military bloc but will receive protection from Washington. Trump made these remarks while speaking at the White House with Vladimir Zelensky ahead of meetings with the Ukrainian leader and his Western European backers.

“No NATO, but we will protect them,” the US president said. On being asked if security guarantees for Kiev could involve US troops, he responded, “We’ll let you know that maybe later today, we’re meeting with the leaders of seven great countries. There will be a lot of help. Europe is the first line of defense because they are there, but we’re going to help, we’ll be involved,” as quoted by Russian News Network RT.

Meanwhile, Special U.S. Envoy Steve Witkoff, who had joined Secretary of State Marco Rubio for the talks Friday at a military base in Alaska, claimed on Sunday (August 17, 2025) that Russian President Vladimir Putin agreed at his summit with Trump to allow the U.S. and its European allies to offer Ukraine a security guarantee resembling NATO's collective defense mandate as part of an eventual deal to end the 3 1/2-year war in Ukraine.


"We were able to win the following concession: that the United States could offer Article 5-like protection, which is one of the real reasons why Ukraine wants to be in NATO," he told CNN's "State of the Union." He added that it "was the first time we had ever heard the Russians agree to that" and called it "game-changing."

What is Article 5 of NATO

Article 5 of NATO's founding treaty enshrines the principle of collective defense, in which an attack on any of its 32 members is considered an attack on all. Joining the Atlantic alliance is a strategic objective for Kyiv that is enshrined in the country's constitution.

“Article 5 provides that if a NATO Ally is the victim of an armed attack, each and every other member of the Alliance will consider this act of violence as an armed attack against all members and will take the actions it deems necessary to assist the Ally attacked,” according to NATO’s official website.

NATO Secretary General Mark Rutte said on Monday (August 18, 2025) that NATO membership for Ukraine was not under discussion but that there was a discussion on "Article 5" type security guarantees for the country that Russia invaded in February 2022.

"The situation is this—that the U.S. and some other countries have said that they are against NATO membership for Ukraine. The official NATO position ... is that there is an irreversible path for Ukraine into NATO," Rutte said during an interview with Fox News.

Can the US attack Russia under Article 5 obligations?

If Ukraine receives protection under NATO’s Article 5, any Russian attack on its land would be seen as an attack on all NATO members. Since the US is a member, it could join the conflict and potentially retaliate against Russia under the article’s terms.

"We will work with Ukraine for long-term peace," says Trump

Kyiv has made joining NATO a central pillar of its response to the escalation of the Ukraine conflict in 2022. Despite multiple pledges from NATO state leaders, no invitation was issued.

Asked about sending peacekeepers, Trump said, “We’re gonna work with Ukraine, we’re gonna work with everybody” to make sure the peace is “very long term.” Zelensky and Western European leaders met Trump and his team at the White House, days after Trump’s summit with Putin in Alaska on Friday, which both sides described as “warm” and “constructive.”