The Russian rouble weakened to a three-week low against the dollar on Tuesday, hampered by relatively low foreign currency sales by exporters at the start of the month.

By 0741 GMT the rouble had lost 0.6% against the dollar at 91.45, its weakest since Nov. 14.

It was down 0.4% at 98.90 versus the euro and shed 0.4% against the yuan to 12.78, touching more than three-week lows against both currencies.

The rouble has now lost support from the month-end tax period, for which Russian exporters usually convert foreign currency into roubles.

But the currency, which enjoyed seven weeks of gains before last week, is relatively strong. It has rebounded from more than 100 to the dollar, thanks to reduced capital outflows since President Vladimir Putin introduced the forced conversion of some foreign currency revenue for exporters in October.

High interest rates are also buttressing the currency. Analysts polled by Reuters expect the Bank of Russia to raise rates to 16% on Dec. 15.

Most economists polled expect the rouble to weaken in 2024.

Brent crude oil, a global benchmark for Russia's main export, was up 0.2% at $78.20 a barrel.

Russian stock indexes were mixed.

The dollar-denominated RTS index was down 0.3% at 1,073.3 points. The rouble-based MOEX Russian index was unchanged at 3,115.5 points. (Reporting by Reuters Writing by Alexander Marrow Editing by David Goodman )