"The $40-per-barrel [scenario] is among likely scenarios that we are looking at," Yudaeva told reporters in Moscow.
The worst scenario previously considered by the Central Bank was the oil price dropping to $60 per barrel.
In November 2014, the Central Bank set an economic scenario assuming that oil prices would not fall far below $80 per barrel up to 2017. The Bank's base scenario suggested that prices would reach $95 per barrel in 2015 and be corrected to $92 per barrel by 2017.
Russia's economy is suffering a slowdown caused mainly by a dramatic decline in oil prices due to oversupply. Prices for Brent oil have fallen from $114 per barrel in mid-June, 2014 to the current $46 per barrel.
Earlier on Wednesday, president of Russia's Sberbank and former Economic Minister German Gref said that world oil prices of $40 per barrel would not last a long time but would remain at level of about $60-$70 for the next few years.
