A European court has agreed to hear a lawsuit by shareholders of the Yukos oil company who are seeking billions of dollars from the Russian government.

The claim is the largest ever to come before the European Court of Human Rights in Strasbourg, the EU Observer reported. The shareholders claim the government seized the company illegally and are asking for 32.5 billion euros ($42 billion).

The company was seized by the government under former President Vladimir Putin and its former chief executive officer Mikhail Khodorkhovsky, who was convicted of fraud and sent to a Siberian prison. Khodorkhovsky had been the richest man in Russia and reportedly had political ambitions that might have made him a rival to Putin.

The company was broken up and sold at auction, with Russian state energy companies buying its most valuable assets.

Shareholders have also made a claim for arbitration at the International Court in The Hague.

The European court expects to hear the case this year.

"This is an important step towards the vindication of the company's belief in the rule of law -- something it never secured in Russia," said Bruce Misamore, the former Yukos chief financial officer, of the court's decision.