A South Korean businessman has been jailed for three years for supplying potentially defective parts to the country's oldest atomic power plant, a court spokesman said Wednesday.

The man, identified only as Hwang, was sentenced last Friday for selling recycled turbine valve parts to the Gori nuclear plant near Busan, the Busan District Court spokesman said.

Hwang, 54, cleaned and painted used parts stolen from the plant's dump by an employee. He then sold them back to the plant, on three occasions since 2008, disguising them as new products.

Hwang pocketed some three billion won ($2.6 million) through the fraud, according to the court.

"The accused deserves heavy punishment for committing a grave crime that could raise serious doubts about the safety of the plant," the judge said in a statement.

The plant employee who stole the scrapped parts, identified only by his family name Shin, was sentenced to three years in prison last month.

There have been previous scandals over potentially defective parts at the country's atomic plants.

Last month the nuclear safety watchdog launched an investigation at Gori and another plant, after they were found to be using components developed by a local company but based on illegally obtained French technology.

The Gori-1 reactor at the plant was also at the centre of a scare in February when it briefly lost mains power and the emergency generator failed to kick in.

The outage was so short that the temperature of the fuel rods remained low. But several officials and engineers have been punished for covering up the incident.

South Korea relies on 21 nuclear reactors to meet about 35 percent of its electricity needs. This month it started work on two more, despite international unease over nuclear power following Japan's Fukushima disaster. ckp/sm/ami/sls