Russian President Vladimir Putin has said he would seek a new six-year term in the country's March elections, in a move that would make him the longest-serving Russian leader since Joseph Stalin.

Opinion polls in Russia indicate Mr Putin will win comfortably, setting the stage for him to extend his dominance of Russia's political landscape into a third decade.

Mr Putin, 65, has been in power, either as president or prime minister, since 2000.

If he wins what would be a fourth presidential term in March, he would be eligible to serve another six years until 2024, when he turns 72.

"I will put forward my candidacy for the post of president of the Russian Federation," Mr Putin told an audience of workers at a car-making factory in the Volga river city of Nizhny Novgorod.

"There's no better place or opportunity to put my candidacy forward. I'm sure that everything will work out for us," he added.

Mr Putin is lauded by allies as a father of the nation figure who has restored national pride and expanded Russia's global clout with interventions in Syria and Ukraine.

His critics accuse him of overseeing a corrupt authoritarian system and of illegally annexing Ukraine's Crimea, a move that has isolated Russia.

Mr Putin’s toughest task will be to mobilise an electorate which shows signs of apathy to ensure a high turnout which in the tightly-controlled limits of the Russian political system is seen to confer legitimacy.

If re-elected next year, Mr Putin will have to choose whether to leave Dmitry Medvedev as prime minister, or appoint someone else.

That decision will trigger a round of intrigue over the succession, as whoever holds the prime minister's post is often viewed as the president's heir apparent.