NATO (Photo via Depositphotos)

NATO is not prepared to wage war against Russia without U.S. support, the leaders of Latvia, Estonia, and Finland have told The Independent.

They believe NATO members need to increase defense spending.

"We are not ready. That's absolutely clear. We can't keep simply hoping for a situation where the US remains much involved in Europe," said Latvian President Edgars Rinkēvičs.

Estonian Prime Minister Kristen Michal emphasized the need to "ramp up defense capabilities" due to the threat posed by Russia and its inability to "operate in a rule-based world."

Finnish President Alexander Stubb linked his country's recent defense acquisitions to concerns over Russia.

"We don't have this because we're worried about Stockholm or London. We have this because we're worried about Moscow," he said.

Finland, Estonia, and Latvia are among NATO members that allocate the most to defense relative to their GDP. Estonia spends 3.4%, Latvia 3.15%, and Finland over 2.4% of GDP on defense.