KIEV, September 20. /TASS/. Ukraine’s energy giant Naftogaz has filed a lawsuit with The Hague court against Russia to recover $5bln for the assets lost in Crimea, the company said in a statement on Wednesday.

"Naftogaz of Ukraine and six companies part of the Naftogaz group - Chernomorneftegaz, Ukrtransgaz, Likvo, Ukrgazdobycha, Ukrtransnafta and Gaz Ukrainy - filed a lawsuit with the tribunal formed under the Permanent Court of Arbitration in The Hague on compensation of losses due to Russia’s illegal seizure of the group’s assets in Crimea," the statement said.

The court is expected to pronounce judgement in this case by late 2018.

International law firm Covington & Burling LLP will represent interests of Naftogaz in court. The company earlier provided legal services to the shareholders of the defunct oil giant Yukos.

After Crimea’s reunification with Russia in March 2014, Ukraine’s companies have already filed seven lawsuits on protecting their investments.

Crimea and Sevastopol adopted declarations of independence on March 11, 2014. They held a referendum on March 16, 2014, in which 96.77% of Crimeans and 95.6% of Sevastopol voters chose to secede from Ukraine and join Russia. President Vladimir Putin signed the reunification treaty on March 18, 2014. The document was ratified by the national legislature, the Federal Assembly, on March 21, 2014. Despite the convincing results of the referendum, Kiev refused to recognize Crimea as part of Russia.