The rouble was 0.6pc weaker against the dollar at 71.22 and had lost 0.7pc to trade at 78.29 versus the euro.
At 1342 GMT, the rouble was 0.6pc weaker against the dollar at 71.22 and had lost 0.7pc to trade at 78.29 versus the euro.
Oil prices fell on concerns that relations between the world's two biggest economies could rattle global business and oil demand already weakened by the coronavirus pandemic.
The rouble could retreat to 72 against the dollar "should we learn that the promised US sanctions against China will be harsh," Sberbank CIB said.
Brent crude oil, a global benchmark for Russia's main export, was down 2.5pc at $35.26 a barrel.
US President Donald Trump said on Tuesday that Washington would announce before the end of the week a strong response to China's planned national security legislation for Hong Kong that would reduce its separate legal status.
The rouble was little affected by two OFZ treasury bond auctions, in which Russia's finance ministry sold bonds maturing in 2023 and 2030 for a combined total of 78.31 billion roubles ($1.10 billion).
Demand for these bonds, which amounted to a total of 108.81 billion roubles on Wednesday, often bolsters the rouble as investors convert foreign currency to take part in the weekly auctions.
The rouble also retains support from the central bank's daily sales of foreign currency. The bank said on Wednesday it had sold $321 million worth of foreign currency on May 22 and May 25.
Additional central bank measures are in focus as it is likely to cut rates next month to support the economy, pummelled by low oil prices and the coronavirus pandemic that has infected more than 370,000 people in the country.
Russian stock indexes were trading lower.
The dollar-denominated RTS index was down 0.9pc to 1,214.1 points, while the rouble-based MOEX Russian index was trading 0.3pc lower at 2,744.1 points.