Japan's nuclear regulator on Tuesday requested the Tokyo Electric Power Co Holdings resubmit safety check applications for its Kashiwazaki-Kariwa nuclear plant after a review of its standards showed past inadequacies had not been properly reported.

Tokyo Electric Power Co.'s Kashiwazaki-Kariwa nuclear power plant is seen in Kashiwazaki in this July 18, 2007 file photo.

The latest request represents a setback to Tepco, which has been trying to restart the plant, based in the country's west, to cut costs associated with acquiring expensive fossil fuels.

The plant was closed along with other nuclear facilities in Japan after a massive earthquake caused meltdowns at its Fukushima-Daiichi nuclear plant in 2011.

Nuclear Regulation Authority Chairman Shunichi Tanaka made the request to resubmit its safety applications directly to Tepco President Naomi Hirose at a meeting at the regulator's office, which was broadcast live on the Internet on Tuesday.

Tepco filed the safety check applications for Kashiwazaki-Kariwa No.6 and No.7 reactors in September 2013 after new safety requirements were imposed following the Fukushima disaster.

The regulator's request relates to Tepco's own analysis that showed a crucial quake-proof building would not be ready to withstand a severe quake by 2014. This building serves as a response center for the two reactors in the event of an accident.

According to a separate Tepco filing to the regulator on Tuesday, while some company staff knew the findings of this analysis, a lack of internal communication meant this was not relayed to the regulator until this year.

Source: Reuters