Russia must pay $2.63 billion (2.7 billion euros) to Yukos Capital after Switzerland's highest court rejected an appeal by Moscow.

Russia had challenged whether the Geneva arbitration court was competent to hear the case brought by the financial arm of Yukos, an independent Russian oil firm that was dismantled and absorbed by the state-held Rosneft.

The court rejected that argument, which was predicated on Russia's parliament having ultimately rejected the Energy Charter treaty that governs cross-border energy trading and investments.

The case was but one part of a vast legal saga concerning the dismantlement of Yukos.

The company broke up in the early 2000s after the arrest of its former owner, the Kremlin critic and ex-tycoon Mikhail Khodorkovsky, and Rosneft came away with most of its assets following a murky auction process.

Khodorkovsky had become a vocal critic of Russian President Vladimir Putin, spent a decade in jail before he was pardoned and allowed to go into exile.

A case brought by Yukos investors has been bouncing around the Dutch courts, with the supreme court last year scrapping an order for Russia to pay $50 billion and sending it back to lower courts.