Ukraine’s vast but murky energy market has traditionally been ruled by domestic groups and Russian giants.

Russian oil companies snapped up the country’s top oil refineries nearly a decade ago, and have since built up western-style petrol station chains. Privatisations in the 1990s put many electricity utilities into private hands. The heavily-politicised natural gas production, supply and transit business is de facto controlled by a state holding, but Russia’s Gazprom wields much influence along with Ukrainian business groups that feed on lucrative inside deals.