Output at Russian gas giant OAO Gazprom (GAZP.RS) fell 34.5% in May to 30.377 billion cubic meters, the Prime-Tass news agency reported Tuesday, citing Ministry of Industry and Energy statistics.
Gazprom has been forced to lower output this year in response to a slump in demand in Europe and in Russia.
In late April, Gazprom said it planned to produce 492 billion cubic meters of gas in 2009, a 0.1% increase on the 550.587 billion cubic meters in 2008.
European demand is expected to pick up later this year as gas prices, which are pegged to the oil price with a six-to-nine month lag, will fall.
Gazprom supplies a quarter of Europe's gas needs.