* Key rates cut by 50 bps effective April 24
* Move enabled by lower inflation
* Aimed to help economy through recession
* Rouble, stocks strengthen
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By Toni Vorobyova
MOSCOW, April 23 (Reuters) - Russia's central bank announced interest rate cuts on Thursday that are expected to herald a series of moves to support the economy through its deepest crisis in a decade.
Some 1.8 million Russians have lost their jobs in the first three months of the year in a recession that raises the risk of social unrest and presents a major challenge for Russia's rulers after years of fast growth fuelled by oil wealth.
The 50 basis point cut to key rates was in line with expectations, but came slightly sooner than forecast -- most analysts polled by Reuters on Wednesday said the move would come in early May.
"It's probably (explained by) a desire to signal to markets and to banks that the central bank is moving to a policy of lowering interest rates," said Stanislav Ponomarenko, head of Russian research at ING.
"We have not yet had (inflation) data for April. It would have probably been more correct to move after those figures."
However, falling global demand and oil prices are pushing Russia's economy into its first recession since the 1998 sovereign default. Combined with the drying up of the global credit market, this has left many companies struggling to refinance foreign debt.
Businesses have called for lower official rates in the hope that it will also translate into cheaper loans for them.
The central bank said it would cut its key refinancing rate to 12.5 percent from 13.0 percent with effect from April 24. The minimum one-day repo rate will be cut to 9.5 percent from 10.0.
The announcement came a day after Prime Minister Vladimir Putin said slowing inflation could allow Russia to cut rates.
Consumer prices rose 0.6 percent in the first 20 days of April, compared with 1.3 percent in the whole of March and 1.7 percent in February.
CONFIDENT ON INFLATION
The central bank, which does not pre-announce the dates of its rate-setting meetings, did not specify a reason for the rate cut in its statement.
It said it would delay a planned rise in mandatory reserve requirements. The reserves on key commercial banks' liabilities will rise by 0.5 percentage points to 1.0 percent from May 1 and by another 0.5 percentage points each month to Aug. 1.
It had previously planned two one percentage point increases to the requirements, one in May and one in June.
"None of the measures announced today are aggressive in our view. However, insofar as this is only the beginning of a process -- in particular regarding interest rates -- this is a clear signal by the central bank that it is looking to gradually return to normality," said Zsolt Papp, chief economist at KBC.
"It implies to us that the central bank is confident that inflation will slow in the second half of 2009 and in 2010 ... We see scope for further gradual interest rate cuts, barring major adverse surprises on inflation."
Analysts expect the refinancing rate will come down to 11 percent by the end of the year, according to the Reuters poll.
The Russian rouble strengthened by around 0.5 percent versus a euro-dollar basket to 38.30 roubles. The benchmark RTS index extended gains after the rate cut announcement to trade 2.4 percent up by 0858 GMT.
"The signal is positive for stock markets, but I don't think it is a big reason for optimism there," said ING's Ponomarenko.
(Editing by Ruth Pitchford)