Russia expects the European Union to prioritize mutual interests while investigating the suspected violations of anti-monopoly rules by the gas giant Gazprom, a deputy foreign minister said on Wednesday.

Alexander Grushko reiterated Moscow’s concerns about the probe, which can affect Russia-EU energy cooperation, “the basis of our economic ties in the past ten years.”

“The sphere of gas purchases requires a very balanced approach,” he said.

Last week the European Commission, the EU's executive arm, launched a probe into three suspected violations of anti-monopoly regulations by Russia’s gas giant in Central and Eastern Europe, which could affect Gazprom’s $60 billion gas export business in Europe.

Gazprom, which considers the probe an effort by the EC to pressure Russia into lowering gas prices, could face a fine of up to ten percent of its annual revenue - about ten billion euro - if the suspected violations are proved.

In a move to protect the gas giant, President Vladimir Putin signed a decree on Tuesday expanding the government’s ability to assist major Russian companies that face investigations abroad.