The rouble firmed on Thursday, moving past the 80 mark against a broadly stronger dollar, supported by relatively high oil prices and the promise of month-end tax payments that usually buttress the Russian currency.

At 0827 GMT, the rouble was 0.2% stronger against the dollar at 79.95 and had gained 0.6% to trade at 85.87 versus the euro.

It had firmed 0.4% against the yuan to 11.28. Month-end tax payments, which usually lead exporters to convert foreign currency revenue to meet local liabilities, should provide the rouble with some support.

Those taxes are due on May 29.

“The current tax period peaks on Monday and foreign currency selling could increase in the short term, which could provide support for the (dollar-rouble currency pair) moving below the 80 mark,” said Bank St Petersburg analysts in a note.

The Kremlin’s plan to introduce a $1 billion monthly cap from June on the amount of foreign currency residents can buy on the domestic market to settle transactions with exiting foreign firms should support the rouble, Rosbank analysts have said, expecting the currency to strengthen to 73-75 in the coming months.

Russian rouble edges up as oil prices rise, tax payments approach

Brent crude oil, a global benchmark for Russia’s main export, was down 0.7% at $77.83 a barrel, but near its strongest point since early May. Russian stock indexes were mixed.

The dollar-denominated RTS index was unchanged at 1,044.0 points.

The rouble-based MOEX Russian index was 0.2% lower at 2,649.0 points.