The move was not anticipated by industry observers in Moscow, who had expected Sechin to wait for some time to arrange a suitable replacement.
According to Rosneft, Sechin quoted a 2 April resolution by Russian President Dmitry Medvedev as the reason for his decision.
In the resolution, Medvedev called for top government officials to leave boards of large state-controlled companies by October to make way for qualified and experienced independent directors.
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