South Korea announced Tuesday plans to open all its 23 nuclear reactors to international inspection in an apparent bid to allay growing public concern over nuclear safety.

The government will start taking bids on Wednesday from international organisations or consortia capable of carrying out such a national survey, with a winner to be announced on May 3, the Ministry of Knowledge Economy said.

The ministry in January had promised nuclear sector reforms after a series of malfunctions, shutdowns and corruption scandals further undermined public confidence already shaken by the 2011 Fukushima disaster in Japan.

The 10-week inspection will look into the safety of all 23 reactors currently in operation and evaluate maintenance procedures at eight sample reactors, the ministry said.

"It will also provide an important chance to improve the safety of the country's reactors down the road," it added.

A survey commissioned by the ministry and published in November showed only 35 percent of South Koreans considered nuclear power to be safe, sharply down from 71 percent in January 2010.

A series of shutdowns and scandals in 2012 triggered a warning from the International Energy Agency in the same month about the need to rebuild public trust.

In May, five senior engineers from the state-run Korea Hydro and Nuclear Power (KHNP) were charged with trying to cover up a potentially dangerous power failure at the country's oldest Gori-1 reactor.

Later in the year, the government shut down two reactors at the Yeonggwang nuclear complex to replace components provided with fake quality certificates.

And a third reactor was taken offline at Yeonggwang when cracks were found on control rod tubes during maintenance work.

The government has vowed to stick with its nuclear power programme and plans to build an additional 16 reactors by 2030.