A Ukrainian court ordered a reduction in the rights of the Norwegian company Telenor on the board of Ukraine`s leading cellphone service provider, Kyivstar, the company said Wednesday, according to Bloomberg.

According to the ruling, Telenor, which owns 56.5 percent of the Ukrainian operator, is to have equal rights with Alfa Group of Russia, which controls 43.5 percent.

Telenor, the largest Norwegian telecommunications group, said it had appealed the ruling in a higher court.

Kyivstar shareholders have been in a dispute over rights since late 2004 and have filed at least a dozen lawsuits against each other.

Telenor and Alfa are also partners in the largest Russian mobile operator, Vimpel-Communications, or VimpelCom, and are locked in a dispute over its growth strategy.

Telenor on Wednesday extended until April 14 its proposal to buy Kyivstar for cash, and for Alfa and Telenor to enter into a market-based separation agreement.

Such an agreement, if triggered, would enable the shareholder placing the highest value on Vipelcom to 100% of the other shareholders’ stake.

VimpelCom is the No. 2 Russian mobile phone company after Mobile TeleSystems.