KIEV, Ukraine (AP) — Former Prime Minister Yulia Tymoshenko said that Ukraine “must be a member of NATO” in order to protect itself from Russian aggression.

Tymoshenko, who is running in the May 25 presidential election, told The Associated Press in an interview Saturday that while only a minority of Ukrainians supported NATO membership previously, Russia’s aggressive actions in the country’s east had forced a “fundamental change” in public thinking.