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MOSCOW, Sep 25 (Reuters) - Russian stocks were mixed on Thursday as a court decision to leave one of the country's best-known tycoons under house arrest dented sentiment that had been lifted by hopes the EU may soon soften sanctions against Russia.
At 0930 GMT, the rouble-based MICEX share index was 0.4 percent higher at 1,447 points, while the dollar-denominated RTS index was down 0.4 percent at 1,185 points, hurt by a significant weakening of the rouble.
Most individual stocks, priced in roubles, were in positive territory. Gas giant Gazprom was up 0.2 percent, oil major Rosneft was up 0.3 percent, and retailer Magnit was 0.7 percent higher, while leading bank Sberbank was flat.
Stocks had continued to rally for a third day in the morning, lifted by hopes that the EU may soften its sanctions against Russia as a ceasefire in eastern Ukraine holds up.
However, the indexes took a knock in the afternoon after a Moscow court rejected an appeal by Vladimir Yevtushenkov, chairman of the Sistema conglomerate.
The court ruled that the tycoon should stay under house arrest until at least Nov. 16 - dashing investor hopes that he might be released on bail.
Yevtushenkov was put under house arrest last week on suspicion of money laundering in Sistema's acquisition of oil producer Bashneft. The case has caused widespread concern among the business community and is being closely watched by investors.
Sistema's shares fell 8 percent on the news, which also served to upset the generally positive mood on the stock market linked to easing tensions over Ukraine.
The European Union imposed stiffer sanctions over Russia's actions in Ukraine earlier this month. However, EU officials said at the time that they would review all punitive measures against Russia at the end of this month following an assessment of the ceasefire in eastern Ukraine.
On Thursday Ukraine's President Petro Poroshenko gave an upbeat assessment of the three-week old ceasefire, saying that it "has finally begun working", with no deaths or wounded reported in the preceding 24 hours.
VTB24 analyst Stanislav Kleshchev said in a note that the Russian market is being encouraged by "a notable softening of the West's rhetoric in relation to Russia."
He said that a speech by U.S. President Barack Obama to the U.N. Security Council on Wednesday was being interpreted positively as Obama also referred to the possibility of sanctions against Russia being lifted.
"A change of tone is clear," Kleshchev commented. "The carrot isn't being offered yet, but the stick has already been put aside."
The rejection of Yevtushenkov's appeal also hurt the rouble, which was already down on Thursday morning, following strong gains on Wednesday driven by demand for local currency to pay a monthly mineral extraction tax falling due on Thursday.
The rouble fell most against the dollar, which was trading at a four-year high globally after strong U.S. housing data on Wednesday, and ahead of durable goods data on Thursday that will be watched for confirmation of the U.S. economy's strength.
The rouble was 0.86 percent weaker against the dollar at 38.48 and lost 0.47 percent to 49 versus the euro .
This has left the currency 0.69 percent weaker at 43.22 against the dollar-euro basket the central bank uses to gauge the rouble's nominal exchange rate.
For rouble poll data see
For Russian equities guide see
For Russian treasury bonds see
Russia in graphics: link.reuters.com/dun63s (Reporting By Jason Bush; Editing by Susan Fenton)