MOSCOW, March 28 - RAPSI. The US District Court for the Southern District of New York has dismissed complaints against several US companies in former Ukrainian Prime Minister Yulia Tymoshenko's lawsuit against RosUkrEnergo and its co-owner Dmytro Firtash, Kommersant Ukraine writes.

RosUkrEnergo is a Swiss-registered venture company that transports natural gas from Turkmenistan to East European countries. 50% of the company is owned by Gazprom, through its daughter Swiss-registered Rosgas Holding A.G., and another 50% by Swiss-registered private company Centragas Holding A.G., acting on behalf of a consortium of GDF Groupowned by Dmytro Firtash and Ivan Fursin.

Experts say the court decision may ultimately lead to the dismissal of the entire case for lack of jurisdiction, but Tymoshenko's lawyers see no grounds for this.

Hon. Alison Nathan made the ruling based on a motion to dismiss the case of April 27, 2012 filed by US companies CMZ Ventures, Dynamic Group, Barbara Ann Holdings (BAH) and Vulcan Properties, as well as by private individuals Paul Manafort and Brad Zackson.

The judge ruled that the plaintiff's (Tymoshenko's) arguments were insufficient for charging US parties with involvement in Tymoshenko's imprisonment or with contributing to the fraud schemes as described by the plaintiff.

One of the above companies told Kommersant they consider Tymoshenko's lawsuit to be groundless, badly prepared and lacking in any arguments.

The lawsuit against RosUkrEnergo was filed in April 2011 on behalf of Tymoshenko, the people of Ukraine and a group of opposition politicians kept under detention or prosecuted by the investigative authorities. The plaintiffs claim that influential circles in Ukraine have established complex money laundering scheme abroad and a scheme to bribe Ukrainian officials.

Tymoshenko claimed that RUE invested "substantial gas revenues" in US and European companies through "a labyrinth of shell companies, including the defendants BAH, CMZ, Dynamic and Vulcan."

The plaintiffs maintain that the authorities persecute anyone who stands in their path.

Tymoshenko has extended the list of defendants in her lawsuit against RosUkrEnergo and Firtash, which now includes Fuel and Energy Minister Yuriy Boyko, chief of the Security Service Valeriy Khoroshkovsky and Prosecutor General Viktor Pshonka.

The list also names Semyon Mogilevich, whom the FBI has been hunting for years, President Viktor Yanukovych's political consultant Paul Manafort, First Deputy Prosecutor General Renat Kuzmin and prosecutor Lilia Frolova, who represents the prosecution in the trial against Tymoshenko.

The plaintiffs accuse them of corruption, fraud and human rights violations.

Tymoshenko's lawsuit centers on a 2009 gas conflict after negotiations stalled between Kiev and Moscow on gas supplies to Ukraine and gas transit to Europe.  In the absence of a supply contract, Russia stopped supplying gas to Ukraine and then to Europe as Kiev started siphoning off gas for its own needs.

Russia's Gazprom and Ukraine's Naftogaz refused mediators' services, particularly RosUkrEnergo, which eventually contested the ownership of 11 billion cubic meters of gas in the Arbitration Institute of the Stockholm Chamber of Commerce.

In October 2011, Tymoshenko was sentenced to seven years in prison for abuse of power based on a 2009 gas contract that she signed with Russia.

In late March, a second case bringing further charges against Tymoshenko was filed with Kharkiv's Kievsky District Court. The case deals with her activity at United Energy Systems. She has also been accused of misappropriating funds.