One of Russia's leading oil companies is asking the High Court in London for an urgent order to stop the Government introducing in the UK this weekend sweeping new economic sanctions announced by the US and Europe.
Lawyers for OJSC Rosneft Oil Company are seeking a "stay" on the sanctions, which are due to take effect in Britain on Saturday (November 29), until their legality can be challenged in an application for judicial review.
The measures, aimed at increasing pressure on the Russians over the Ukraine, are due to be brought into force through secondary legislation as part of the European-wide ban on providing services for oil exploration and production in Russia.
The bans will prevent previously active companies such as Exxon and Shell from dealing with five of the largest Russian oil producers and pipeline operators: Gazprom, Gazprom Neft, LukOil, Surgutneftegas, and Rosneft.
Rosneft intends to argue at its judicial review application that the UK orders being used to extend existing sanctions in line with EU regulations are unlawful and should be quashed.
Pushpinder Saini QC, appearing for Rosneft, told two judges that the effect of the new legislation was to make it a criminal offence to breach the prohibitions.
But the legislation coming into force on Saturday is "riddled with uncertainties as to definition and scope" and the Government is still waiting for clarification from the EU legislature.
He said of the decision to bring the new legislation into force this weekend: "There is no EU obligation that says it has to come into force on a particular day."
Mr Saini said the principle that there had to be legal certainty over criminal offences was of constitutional importance and went back 400-500 years.
He argued: "At this stage there is a strong argument that the principle of legal certainty has been violated, or will be violated.
"Nothing in EU law requires the UK to create a criminal offence with this lack of legal certainty."