Russian actor Artur Smolyaninov was the star of one of President Vladimir Putin's favourite films -- about a Soviet unit making a last-ditch stand against Afghan insurgents. Now he is classified as a "foreign agent" and faces criminal investigation.

Smolyaninov was the hero of "Devyataya Rota" (The 9th Company), a Russian feature film that came out in 2005. He played the part of the last soldier standing during a battle in Afghanistan, which Soviet forces occupied for a decade. He was often described as Russia's Rambo, a nod to the US action movies starring Sylvester Stallone.

Much has changed since then. Smolyaninov is in exile and in a recent interview said he was prepared to fight on Ukraine's side and kill Russian soldiers. He told Novaya Gazeta last week: "I feel nothing but hatred to the people on the other (Russian) side of the frontline. And if I were there on the ground, there'd be no mercy."

He said a former colleague had gone to fight on the Russian side. "Would I shoot him? Without any doubt! Do I keep my options to go fight for Ukraine open? Absolutely! This is the only way for me. And if I were to go to this war, I would only fight for Ukraine."

A few days later, the Russian Ministry of Justice classified the actor as a foreign agent.

Alexander Bastrykin, the head of the Russia's Investigative Committee, also ordered that a criminal case be opened against Smolyaninov.

Smolyaninov has been highly critical of the campaign in Ukraine. He recently recorded a Soviet-era song -- Temnaya Noch (Dark Night) -- with reworked lyrics.

It included the lines: "Take a look, occupier, How maternity homes are without power, How children sit in shelters. And how books are drowned. The Russian night Has reached schools and hospitals."

Another verse referred to "a bunker, Where one Führer hides, And a bald little cook, Feeds the Fuhrer from a spoon." The cook was a reference to Yevgeny Prigozhin, who runs the Wagner private military company and won catering contracts from the Kremlin.

When he first spoke out against the war last summer, Smolyaninov, who at the time he was in Russia, told an interviewer it was "a catastrophe, everything collapsed: ashes, smoke, stench, tears."

Last October, a Moscow district court imposed a fine of 30,000 rubles (430 US dollars) against Smolyaninov on charges of discrediting the Russian armed forces. That same month, he left Russia and is thought to be in Latvia at present.

Smolyaninov recounted how he'd crossed the Russian border into Norway. "I crossed the border on foot... You just walk 30 meters and there are completely different people in front of you. They are so soft. Even the look is different."

The film "Devyataya Rota" was so popular that Putin welcomed the actors and crew, including Smolyaninov to his residence outside Moscow in November 2005, where he put on a special showing of the movie.

The Kremlin said that after watching the film, Putin talked with director Fyodor Bondarchuk and the leading actors, including Smolyaninov.

Russian state news agency RIA Novosti reported at the time that Putin declared that the film "takes the soul, you immerse yourself in the film."

"The film is very strong, such a real serious thing about the war and people who found themselves in extreme conditions in this war and showed themselves very worthy," Putin said at the time.

The Russian Justice Ministry has added a number of others to its list of foreign agents in recent days, including music critic Artemy Troitsky and several journalists.

"These people were put on the register under article 7 of Russian law on the control of the activities of persons under foreign influence," according to Russian state news agency TASS.

It was also reported this weekend that two well-known theatrical actors had been fired from the Chekhov Moscow Art Theater for criticizing the war in Ukraine. Dmitry Nazarov and his wife Olga Vasilyeva were dismissed by the artistic director of the theater, Konstantin Khabensky, who accused the actors of "anti-Russian sentiments."

The state news agency TASS confirmed the duo had been fired, without specifying a reason.