President Vladimir Putin said the incident was the result of a chain of tragic and chance circumstances, in comments that appeared to defuse the situation somewhat. Earlier the Russian Defence Ministry said the plane was shot down by Syrian anti-aircraft systems but it also accused Israel of indirectly causing the incident.

At 1519 GMT the rouble was 0.91 percent stronger against the dollar at 67.44 and had gained 0.81 percent to trade at 78.85 versus the euro.

Brent crude oil, a global benchmark for Russia's main export, was up 1.6 percent at $79.3 per barrel on signs that OPEC would not be prepared to raise output to address shrinking supplies from Iran, and as Saudi Arabia signalled it was in no rush to bring prices down.

The rouble was also supported by a resumption of positive dynamics in Russia's debt market, analysts at BCS brokerage said. Russia's Finance Ministry said it would not hold its weekly OFZ treasury bond auctions on Sept. 19 in order to stabilise the domestic debt market.

BCS brokerage said developments around aluminium giant Rusal may have helped the Russian currency. Washington's recent decision to give Rusal, hit by US sanctions, some room for new supply contracts has been interpreted by some market players as a signal that the next wave of US sanctions against Russia could be easier than expected, BCS said.

"The rouble may get some room for appreciation in the coming days because the peak of tax payments is approaching (September 25) and no concrete news on the sanctions issue is expected in the coming days," said Tatyana Yevdokimova at Nordea.

The Russian central bank's decision last week not to buy foreign currency on the market until the end of this year is helping to reduce the volatility in the rouble trade, Yevdokimova added.

Russian stock indexes were up. The dollar-denominated RTS index was up 2.0 percent to 1,121.47 points, while the rouble-based MOEX Russian index rose 1.2 percent and reached a record level of 2,400.13 points.