The committee was due to meet on Tuesday to discuss the United States' international sanctions programmes on North Korea, Iran and Venezuela, "with a particular focus on Russia".

But a short notice on its website said the meeting had been postponed until an unspecified date, without giving any other explanation.

The rouble, already boosted by higher oil prices, rose further after the postponement and was 0.4 percent stronger against the dollar at 65.59 and also 0.4 percent stronger against the euro at 73.96 by 1056 GMT.

It would have strengthened even further if it had not been for gains in the US dollar, Artem Zvonarev, a trader at VTB Capital in Moscow, said.

"Gains in the rouble that are driven by positive factors, such Russia's sovereign rating upgrade or the postponement of the US congress hearing, are now capped by the situation on the global forex market where the dollar has been strengthening lately against other currencies," Zvonarev added.

Traders were also watching the weekly auctions of OFZ government bonds after the finance ministry said last week it was considering scrapping its usual practice of setting a maximum amount of paper on offer.

"As we interpret it, the ministry is trying to avoid spooking investors at all costs if the ambitious 2.4 trillion rouble borrowing plan is to be accomplished," analysts at Rosbank said in a note.

Brent crude oil, a global benchmark for Russia's main export, was up 1.8 percent at $62.6 a barrel.

The dollar-denominated RTS stock index rose 0.9 percent to 1,212.2 points and the rouble-based MOEX Russian index rose 0.6 percent to 2,523.9 points.