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KIEV, Dec 18 (Reuters) - Ukraine's central bank will sell dollars at a currency auction on Thursday at 8.95 hryvnias and on Friday at 8.7 hryvnias, Finance Minister Viktor Pynzenyk said.
Central Bank Chairman Volodymyr Stelmakh said the bank would also cut money supply by increasing its key discount rate from 12 percent, although he did not say how far the rate would be raised.
Pynzenyk added that the overnight refinancing rate would also be raised.
The central bank has been battling to stem the fall of the hryvnia, which has halved in value since September when the global financial crisis took hold of Ukraine's economy. It was quoted at historic lows of 9.1-9.5 per dollar on Thursday.
"The central bank will come to the market and sell dollars at 8.95," Pynzenyk said in televised comments from Kiev airport, where he met Stelmakh and President Viktor Yushchenko.
"Tomorrow, the central bank will again enter the market and sell dollars at 8.7. At the same time, and this is important, the official rate of the dollar is not changing," Pynzenyk said.
The official rate on Thursday was 7.8648 hryvnias to the dollar.
The IMF agreed to lend the equivalent of $17.1 billion to Ukraine subject to conditions, including that the official currency rate can only vary by 2 percent from the market rate.
The bank last changed the discount rate in April, raising it to 12 percent from 10 percent. Overnight rates were at 18 percent and 20 percent for unsecured deposits. (Editing by Mike Peacock)