The timing of the announcement, which was a certainty after Putin revealed in September that he planned to return to the Kremlin next year, appears to be aimed at giving the party a boost in parliamentary elections next Sunday.

Prime Minister Vladimir Putin gestures as he speaks during a United Russia party congress in Moscow, Russia, Sunday, Nov. 27, 2011. Prime Minister Vladimir Putin has been formally nominated by the ruling United Russia party to run for president in next March's election. [Xinhua]

Putin accepted the nomination before it was even subject to a final vote at a United Russia Party congress also attended by President Dmitry Medvedev.

Putin and Medvedev have announced plans to swap jobs next year.