* Deputy Prime Minister Igor Sechin leaving Rosneft board
* Control to stay in Sechin's hands-Rosneft chief
* President Medvedev has ordered board purge for state cos
(Adds quotes, details; corrects typo in bullet point)
By Darya Korsunskaya
MOSCOW, April 15 (Reuters) - Russian energy tsar Igor Sechin will call the shots at Rosneft despite stepping down as chairman, the company's president said, casting doubt on whether a directive by President Dmitry Medvedev has teeth.
Medvedev last month ordered Prime Minister Vladimir Putin's deputies and cabinet ministers to leave the boards of state firms, a move that he said would increase the companies' effectiveness and transparency.
"Sechin will keep control, and I believe he will even strengthen it," Rosneft's Eduard Khudainatov said on Friday on the sidelines of a meeting, which was attended by Putin.
"We are a company with state ownership, and we directly report to the government via orders and other administrative tools. The daily control is in the hands of Igor Ivanovich (Sechin)," he added.
Medvedev ordered Putin to begin the board purge by July 1. But Sechin, a deputy prime minister and close Putin ally who oversees Russia's oil and gas industry, stepped down from his position as Rosneft chairman this week.
Analysts and investors predicted his departure would do little to change Russia's biggest oil company. Rosneft accounts for more than one-fifth of Russia's daily oil production of over 10 million barrels.
Mikhail Alefirenko, a portfolio manager at Pharos Financial Fund, said after Sechin's resignation that it would have "no real impact" on the way Rosneft operates.
He said it was intended "to show the public, international investors, that he is doing something to reform state-owned companies".
Medvedev ordered ministers out as board chairs by October, only five months before a March 2012 presidential vote in which Putin has hinted he may return to the presidency or endorse Medvedev for a new term.
Analysts say the order, one of a series of assertive moves Medvedev has made lately, was aimed at bolstering his image as reformer and a corruption fighter.
(Writing by Jessica Bachman; editing by Steve Gutterman and Jane Baird)