Russian intervention in an European Union anti-trust probe into Gazprom changes nothing in the case which goes ahead in the best interests of the bloc, Competition Commissioner Joaquin Almunia said Monday.

Almunia told AFP the EU understood very well the importance of gas supplies in
Europe , with Russia accounting for some 25%, but "our responsibility is to the single European market."

The regulators' task "is to apply the competition rules regardless of who are the shareholders of the companies, of the sectors involved," he said.

The EU launched a probe into Gazprom earlier this month over concerns it was hindering competition in central and eastern European gas markets.

In response, Russian President Vladimir Putin issued a decree under which "strategic Russian companies" such as Gazprom working abroad should not change pricing contracts or disclose information without
Moscow 's approval.

"We continue our (Gazprom) investigation without any special limitations," Almunia said, stressing that the inquiry was routine and like any other.

"The decisions we have taken and will take must be based exclusively on an assessment of the competition issues," he added.