The Russian rouble firmed around 4 per cent against the dollar and euro on Monday, heading back towards multi-year highs hit last week, supported by capital controls and an upcoming month-end tax period.

By 1050 GMT, the rouble was 4 per cent stronger against the dollar at 57.85, not far from 57.0750, its strongest mark since late March 2018, hit on Friday.

It had gained 4.4 per cent to trade at 60.05 versus the euro, nearing its strongest point since June 2015 of 59.02, also reached on Friday.

The rouble has firmed about 30 per cent against the dollar this year despite a full-scale economic crisis in Russia, making it the world's best-performing currency - albeit artificially supported by controls imposed in late February to shield Russia's financial sector after its decision to send tens of thousands of troops into Ukraine prompted unprecedented Western sanctions.

The rouble is being driven by export-focused companies that are obliged to convert their foreign currency revenue after the sanctions froze nearly half of Russia's gold and forex reserves.