Russian energy giant Gazprom and Austrian oil and gas company OMV signed a supplement to a contract increasing gas supplies to Austria by 1 billion cubic meters per year, Gazprom said in a news release published on Monday.

Chairman of the Gazprom Management Committee Alexey Miller and Chairman of the Executive Board of OMV Rainer Seele signed the document at their working meeting in the Russian city of St. Petersburg, according to the news release.

The updated volume of gas supplies to Austria will be carried out throughout the entire contract period, it said.

"The signing of the document on additional exports beyond the contractual amounts serves as yet another proof of the high demand for Russian gas on the part of our European consumers," Miller said.

The increase of gas supplies contributes to ensuring the security of energy supplies for both Austria and other European countries, Seele said.

Gazprom has been raising its exports to Austria for years, which saw a one-third year-on-year increase in the first ten months of 2018, according to the company.