SEOUL – The safety of South Korea's nuclear reactors "should be improved significantly", although no immediate actions are needed, an international nuclear safety evaluation body said after completing a five-month review of the country's reactors.

Seoul has been hit with a series of nuclear safety scandals since late 2012, when certificates supplied for some reactor parts turned out to be fake. Some reactors have been closed and 100 people indicted in the scandals, while the government has come under pressure to rethink its reliance on nuclear power.

TUV SUD Industrie Service of Germany, called in to review South Korean reactors in May, said in a statement released by the Nuclear Safety and Security Commission on Wednesday that the country's nuclear power plants in general operate in compliance with international standards and regulations.

Still, some 200 findings and recommendations from the review should be implemented to enhance nuclear plant safety. Reactor operator Korea Hydro and Nuclear Power (KHNP) was given a month to prepare an action plan on the recommendations for government approval, the commission said in another statement.

"The safety of Korean power plants should be improved significantly with respect to the reliability of major components integrity, the engineering and maintenance program and the quality assurance program," TUV SUD said.

TUV SUD added that the review identified no need for immediate action by KHNP or the regulatory body. "The identified individual findings and recommendations are in the customary range compared with the international experience," it said.

KHNP, once it receives notice from the commission on the review and recommendations, will work to submit its action proposals within a month, a spokesman for the operator said.

Asia's fourth-largest economy faces severe power shortages this winter due to the nuclear scandal and related closures. About a third of the country's power is generated by its 23 nuclear reactors.

To curb electricity demand, the Korean government said on Tuesday it will hike electricity tariffs in its latest bid to avert power blackouts because of its supply gap.

Currently five reactors are offline including three shut because of control cables supplied with fake safety certificates, according to KHNP's website.

There will be no further forced closures as a result of the review as no immediate action was required, a spokesman for the nuclear commission said.

The Korean government has been criticised for a lack of transparency over the safety of its nuclear programme, and for putting both oversight and promotion of the industry in the hands of the one ministry.

TUV SUD in Wednesday's statement advised an independent third-party agency should be involved in oversight along with the regulatory commission, particularly on safety inspections.

KHNP is owned by state-run power utility Korea Electric Power Corp (KEPCO).