* Initial backing given to law on information about banks
* Opponents say big banks will be protected, depositors at risk
* Kremlin foes see legislation as part of media crackdown
MOSCOW, April 4 (Reuters) - The Russian parliament gave preliminary approval on Friday to legislation limiting publication of information about banks, a move critics said would protect powerful financial institutions but could harm their depositors.
Opponents said the bill proposed by pro-Kremlin lawmakers would deprive depositors of information they need to ensure their financial security, and could be used to crack down on independent media.
Its passage in the first of three votes in the lower house of parliament came after President Vladimir Putin promised support for Bank Rossiya, a bank hit with U.S. sanctions aimed at punishing him and his allies for Russia's annexation of Crimea.
The legislation would enable federal prosecutors to block any website deemed to contain knowingly false information about banks, and impose fines of up to 1 million roubles ($28,300).
Proponents suggested it was needed to prevent banks from being brought down by false information, undermining stability.
"Bankrupting a large financial institution is like shaking the state's foundations and doing severe harm to its financial system and the state itself," Anatoly Aksakov, a deputy in the State Duma lower house, said before the vote.
"Sometimes we need to make serious decisions to prevent such cases," he said.
Opponents said it would protect banks and the state while increasing the risks faced by depositors. They voiced suspicion the authorities would deem any information they feared would undermine trust to be deliberately false in order to suppress it.
"No one needs (the law) except some owners of big banks," said Alexander Tarnavsky, a Duma deputy from left-leaning party Just Russia. "It would be simpler to write that any negative information about Russia's banking system is prohibited."
Some critics said they feared that the law would be used as an instrument to shut down media outlets, part of what Kremlin foes say is a clampdown on dissent that has intensified amid Putin's standoff with the West over Ukraine.
"Undoubtedly, it is a repressive law," said Igor Yakovenko, the former head of the Russian Union of Journalists. "Any financial analysis about banks is becoming tabooed; it may be found false ... The point of this law is that banks are always right," he said.
The bill was approved in the first reading by a 245-92 vote in the 450-seat State Duma with support from the ruling United Russia party, whose chief loyalty is to Putin.
In a show of defiance against the West, Putin promised state support for Bank Rossiya and said he would open an account there after the United States imposed sanctions on it as punishment for his policies toward Ukraine and annexation of its Crimea region.
($1 = 35.2870 Russian Roubles) (Editing by Steve Gutterman and Mark Trevelyan)