MOSCOW: The rouble weakened against the dollar to a two-week low on Thursday as Britain and the Netherlands accused Russia of running a global campaign of cyber attacks.

Dutch authorities said they had disrupted an attempt to hack into the chemical weapons watchdog, and U.S. Defense Secretary Jim Mattis said Russia must be held accountable.

The United States also on Thursday indicted seven Russian intelligence officers for conspiring to hack computers and steal data in a bid to delegitimise international anti-doping organisations.

The news sent the rouble to 66.95 against the dollar, a level last seen on Sept. 19. At 1419 GMT the rouble was 1.55 percent weaker against the dollar at 66.89 and had lost 1.85 percent to trade at 77.04 versus the euro .

The rouble has also been under pressure from a generally stronger dollar. The U.S. currency has been boosted by a spike in Treasury yields because of strong U.S. data and Federal Reserve comments that interest rates may be raised above an estimated "neutral" setting.

Investors are fleeing emerging-market assets and the main guidepost for market participants now is U.S. Treasury yields, said Kirill Tremasov, head of research at Loko-Invest.

Oil slipped from four-year highs reached in the previous session, after sources said Russia and Saudi Arabia struck a private deal in September to raise crude output.

Brent crude oil, a global benchmark for Russia's main export, was down 0.59 percent at $85.76 a barrel.

The market has also priced in the cancellation of one of two Russian treasury bond auctions scheduled for Wednesday, which signalled that market conditions have not yet recovered.

Russian stock indexes declined.

The dollar-denominated RTS index was down 2.93 percent at 1,160.28 points. The rouble-based MOEX Russian index  was 1.15 percent lower at 2,465.25 points.