But with the current approach doing little to change Lukashenko's behaviour, some member states want to widen sanctions criteria to include people who feed the regime money as well as those directly involved in repression or election rigging.

"There will be a discussion on this because the current criteria are too narrow. This case [Bilalitski] shows there is a need for something new," an EU diplomat told EUobserver. "With Lukashenko's best friend in the EU out of the picture, we might have a better chance than in the past," he added, referring to former Italian leader Silvio Berlusconi who fell from power last week.

Italy used to routinely water down EU sanctions against Belarus.

Another EU diplomat said Lukashenko's top financial sponsors are well known: Yury Chizh (health spas, retail); Vladimir Peftiev (arms, lotto, telecoms); Aleksander Moshensky (milk, seafood); Alexander Shakutin (construction); and Paul Topuzidis (retail, tobacco).

The EU imposed a visa ban and asset freeze on Peftiev in summer. But he highlighted the limits of existing criteria by lodging four appeals in August at the EU court in Luxembourg - one in his name, and one each in the names of his three companies.

The verdict is unlikley to come before 2013 and if he wins, he will get little more than a moral victory.

A court spokesman told this website nobody has ever won a financial damages claim against the EU because they were put wrongly on a blacklist. Damages are only awarded for serious violations of EU law. But the court has in the past said it is forgiveable if the EU gets a name wrong in an opaque regime.

Meanwhile, how much pressure the oligarchs can apply to Lukashenko if future EU sanctions hurt their business remains an open question.

Some opposition activists believe they could orchestrate his downfall.

But others say only Moscow poses a threat to the 57-year-old billionaire. "It is not correct to call them oligarchs. Oligarchs by defintion have power. They have no power at all, they have businesses and are totally dependent on Lukashenko," independent Belarusian journalist Andrej Dynko said.