Russia's central bank stepped in to curb the rouble's recent appreciation this week, spending a total of around $4 billion.

Its aim has been to defend the currency around the 36.25 level against the euro-dollar basket the institution uses for guiding its foreign exchange policy.

According to Reuters, the rouble finished 36.29 against the basket on Wednesday (30th September) and 36.24 on Thursday.

Dealers have attributed the rouble's rise to relatively high prices for crude – Russia's chief export – and expect it to keep firming today, in the absence of major global developments affecting it.

Analysts note that the central bank's interventions have enabled it to replenish Russia's gold and foreign exchange reserves, which were depleted during last winter's managed rouble depreciation.

"The rouble remains very underappreciated compared to lots of emerging markets' currencies – investors look at that as well," one dealer remarked to the news provider.

Russia's central bank cut lending rates for the seventh time since April this week, prompting observers to suggest Russia is more concerned with economic growth than inflation.

The bank said the drop by 50 basis points to 10 per cent was necessary since industrial output dropped month-on-month in August.