MOSCOW, Russia (CNN) -- Judges have ordered the closure of Russia's last major independently-owned national television network.

Russia's Higher Arbitration Court ended a legal battle by upholding an original ruling that the station be liquidated because its debts were greater than its assets.

TV6, owned by former Kremlin insider Boris Berezovsky, said it was making money and that the law allowing such suits had been changed.

Berezovsky has become a sharp critic of Russian President Vladimir Putin and is in self-imposed exile in London. He has criticised moves to close the station as politically motivated.

The channel's director, well-known journalist Yevgeny Kiselyov, also maintained the case was politically motivated -- an attempt by the Kremlin to eliminate reporting critical of the government and president.

Lukoil Grant, a pension fund partially owned by the Russian state and a minority shareholder in the station, brought the bankruptcy suit. It said the move, which forced TV6 off the air last November, was simply a business decision.

Many TV6 journalists, including Kiselyov, joined the station after walking out of NTV, another independent station which was taken over by the state-controlled natural gas monopoly, Gazprom, last year.

The takeover was widely criticised as political.

Kiselyov and NTV's then-owner, media magnate Vladimir Gusinsky, accused the gas giant of staging the takeover on the orders of the Kremlin to silence a vocal media critic.

Lukoil Grant used the same argument Gazprom did, that it was simply a business decision.

Pavel Korchagin, chief operation officer for TV6, told CNN the financial reasoning behind his company's closure was "very cynical."

He added: "TV6 is a fast growing company, one of the most popular TV networks in this country."

He said the company would apply against the ruling to an international court.

The TV6 case has raised concern in the West that freedom of the media was under attack yet again. U.S. State Department spokesman Richard Boucher said on Wednesday that his country was urging the Russian government that TV6 get a "full and fair hearing."

The Russian Court's decision is final though TV6 can appeal to the Constitutional Court of Russia. Interfax news agency, quoting a source at TV6, says it plans to appeal against the court ruling through the Supreme Arbitration Court in the European Court of Human Rights.