"The official forecast is still 79 million tons for 2009 but our forecasts include the possibility of a cut of 3 million tons," Bakyt Sultanov told journalists.
Explaining the move, Sultanov said that "if prices are below $40 per barrel several fields could introduce cuts over profitability issues."
Oil prices fell below $35 a barrel in New York on Monday.
Russian Prime Minister Vladimir Putin ordered the Finance Ministry to revise the 2009 state budget based on an average oil price for the year of $41 per barrel.