MOSCOW (Reuters) – The Russian ruble weakened to a 10-month low against the dollar during Tuesday’s trading session following Ukraine’s surprise attack on Russia’s Kursk region a week ago, but then rebounded to its opening level.

At 15:00 GMT, the ruble was trading at 90.99 per dollar, after falling to 96.60, its lowest level since October 20, 2023, according to LSEG data. The ruble has lost 6.2% since the attack began on August 6.

Trading in major currencies has moved to the over-the-counter (OTC) market, making access to price data complex. This happened after the June 12 introduction of Western sanctions against the Moscow Stock Exchange and its clearing agent, the National Settlement Center.

One-day futures contracts for the ruble and dollar, which are traded on the Moscow Exchange and serve as a guide for OTC rates, fell 0.4% to 89.60 on Tuesday. Futures fell 2.5% during the previous trading day.

The central bank’s official exchange rate, calculated based on OTC data, was set at 92.65 on Wednesday, up 3% from the rate set on Tuesday.

The ruble’s weakening against the dollar and euro has continued despite support from higher oil prices and increased daily net sales of the yuan by the central bank and the finance ministry.

The ruble had weakened 1.3% to 12.07 against the , which became the most-traded foreign currency in Moscow, by 15:00 GMT, according to OTC market analysis. In trading, the ruble hit 12.11 against the yuan, its weakest since June 24.

It fell 0.2% to 99.70 against the euro, according to LSEG data. The central bank’s official exchange rate was 96.69 rubles per euro.

Oil, the global benchmark for Russia’s main export, fell 1.0% to $81.24 a barrel as markets relaxed the risk of war in the Middle East.