The main opposition party said Wednesday it will press criminal charges against those who were involved in the controversial early closure of a nuclear power plant and the alleged obstruction of the state audit into the case.

"(The party) will report (to the law enforcement) all related officials who obstructed the inspection in the process of the unfair closure, abused authority and destroyed official documents on criminal charges," Rep. Joo Ho-young, the floor leader of the People Power Party (PPP), said in a party meeting.

On Tuesday, the Board of Audit and Inspection (BAI) announced the result of its audit into the early closure of the Wolsong-1 nuclear power plant in Gyeongju, 370 kilometers southeast of Seoul.

The government watchdog concluded that the economic viability of the country's second-oldest nuclear reactor was unreasonably undervalued serving as a factor in determining the reactor's early closure.

Last week, the BAI chief Choe Jae-hyeong told lawmakers during a regular parliamentary audit of his agency that trade ministry officials obstructed its audit of the case by destroying related official documents.       

Joo said, "The fact that government officials, including former Industry Minister Paik Un-gyu, discarded 444 reactor-related documents on the eve of an inspection symbolically shows that the closure was the wrong decision."

He said President Moon Jae-in's alleged single remark in 2018 to one of his aides, "When will Wolsong-1 come to a stop?" set off the process leading to the "unlawful, unwarranted" closure of the reactor.

"If (Moon) is found to have any culpability (for the closure), he will be unable to evade it even after his retirement," he noted.

The initial 30-year operational life cycle of Wolsong-1 terminated in 2012. But the nuclear power plant was brought back into operation to run for another 10 years to 2022 during the previous Park Geun-hye administration.

The Moon administration, however, decided in 2017 to decommission it earlier than scheduled in line with the president's nuclear-free energy policy vision, triggering a fierce spat with pro-nuclear energy politicians and experts. (Yonhap)