The Soviet Union, the world's largest oil producer, will be forced to import crude oil within two years unless it can revive its flagging petroleum industry, the Communist Party daily Pravda said Monday.

The newspaper said 1990 output from the huge Tyumen oil field in western Siberia was 40 million tons below the 1988 level of 394 million tons."According to estimates by specialists, Tyumen supplies about half of the country's 61 million tons of oil exports," Pravda said.

"If this situation continues in the future, already by 1993 the Soviet Union will have to purchase oil abroad. How then will we pay back the credits so generously extended to us?"

Soviet output has declined in the last 18 months because of a decaying infrastructure and political and economic turmoil.

Last year it averaged an estimated 11.4 million barrels a day, down 0.7 million barrels a day from 1989, the Paris-based International Energy Agency said in January.

Soviet President Mikhail Gorbachev last month ordered specialists to prepare measures to improve technical supplies and working conditions in the oil industry.

Pravda said Gorbachev supported plans to "demonopolize" the oil industry by giving local governments more control over their energy resources and introducing free-market principles.

"Healthy competition among them would improve matters," Pravda quoted Gorbachev as saying.

As part of the move to a market-based economy, the government plans to adjust domestic oil and gas prices gradually until they reflect world prices, the newspaper said.