MOSCOW--The Russian ruble slid to yet another all-time low against the euro-dollar basket of currencies as investors wait for the latest report on the country's creditworthiness from Standard & Poor's Inc., expected later Friday.

S&P has Russia's low investment-grade credit rating on negative watch.

Any downgrade would make the country's government bonds non investment grade, otherwise known as "junk".

The ruble, battered this month by sliding oil prices, had eased 0.2% to its weakest ever level of 46.8 against the euro-dollar basket in the first minutes of trade on the Moscow exchange.

The central bank, which uses the basket to track the domestic currency market, said Friday it shifted the ruble's trading band to 37.70-46.70 closer to the end of the main trading session on Thursday.

The ruble's trading levels now suggest that the central bank has moved the band 48 times so far this month, shifting it by 5 kopecks each time after selling $350 million on the lower end of the corridor, according to the intervention rule. This takes intervention spent on supporting the plummeting ruble to as much as $16.8 billion since early October.

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