MOSCOW: The Russian ruble and stocks jumped on Friday, rebounding with the oil price as global market sentiment shifted abruptly after weeks of fears linked to slumping oil prices.

At 1530 GMT, the ruble was 5 percent stronger against the dollar at 78.33 and had gained 5.6 percent to 84.69 versus the euro.

The dollar-denominated RTS stock index was up 9.4 percent to 692 points, while the ruble-based MICEX was 2.5 percent higher at 1,718 points.

The rebound came the day after the ruble hit its lowest ever level against the dollar, 86 rubles per dollar, illustrating the extreme swings in sentiment caused by uncertainty over the oil price and global economic prospects.

Brent crude oil, a global benchmark for Russia's main export, was up 8.2 percent at $31.7 a barrel, boosted by cold weather and hints of fresh monetary stimulus from the European Central Bank.

Analysts and traders cautioned, however, that the ruble's rally may be short-lived given lack of evidence the trend for oil prices to keep falling had been permanently reversed.

"Volatility is extreme, and we would suggest that rationally predicting the direction of the next 5 percent move in USD/RUB is almost impossible," analysts at Sberbank CIB said. "Ruble moves remain highly tied to oil fluctuations."

Dmitry Polevoy, chief Russia economist at ING, said Thursday's sharp move down had been mostly driven by financial market trading strategies.

"There is still a lack of strong natural flows against the ruble, unlike in 2014," he said, referring to purchases of foreign currency by companies and households.

The scale of Thursday's plunge had been reinforced by stop losses — pre-arranged orders to sell when a certain level is reached — Polevoy said.

Other analysts drew attention to a shift in rhetoric by the central bank, following comments on Thursday that many market players had interpreted as a sign of indifference to the ruble's plunge.

On Friday, central bank head Elvira Nabiullina said the economic situation needed quick responses and that the central bank had all the tools needed to ensure financial stability.