Exiled Russian opposition leader Yulia Navalnaya urged supporters Tuesday to keep up the fight against President Vladimir Putin, describing him on the day of his re-inauguration as a murderous tyrant.

"Our country is currently being led by a liar, a thief and a murderer, but this will definitely come to an end. Don't give up, truth will prevail," Navalnaya said in a video published on YouTube shortly before the Kremlin ceremony in which Putin took the oath of office for a new six-year term.

Based outside Russia, Navalnaya has vowed to continue the work of her late husband Alexei Navalny, who died in an Arctic penal colony Feb. 16. She has accused Putin of having him killed, an accusation the Kremlin denies.

Navalnaya said Putin's war in Ukraine and his jailing of political opponents had made a mockery of his promises at past inaugurations to deliver peace and prosperity to Russia and protect the rights and freedoms of its people.

"Huge sums of money are stolen from all of us every day to fund bombings of peaceful cities, riot police beating people with batons, propagandists spreading lies. And also for (the elite's) own palaces, yachts and private jets," she said.

"And as long as this continues, we can't stop the fight."

Putin won a huge landslide in a tightly controlled election in March. The Kremlin said the vote demonstrated that Russians are overwhelmingly united behind him, and portrays Navalnaya and supporters of her late husband as Western-backed extremists bent on trying to destabilize the country.

With Navalny dead and other leading Kremlin critics in prison or exile, opposition inside Russia has been effectively crushed. Navalnaya acknowledged the struggle was hard, but urged people to unite in opposition to corruption and against the war.

"With each of his terms, everything only gets worse, and its' frightening to imagine what else will happen while Putin remains in power," she said. "With him at the helm, our country will have neither peace, nor development, nor freedom.

"We must ensure that no one in the world believes Putin – neither in Russia nor beyond its borders."