The operator of the disaster-hit Fukushima nuclear plant could voluntarily split itself up into separate firms as part of the government's drive to deregulate the energy market, a newspaper said Friday.

Under the plan, Tokyo Electric Power (TEPCO) would set up a holding company under which three separate subsidiaries would be formed -- an operator of fossil-fuel power plants, a managing firm for the grid and an electricity retailer -- by the end of March 2017, the Nikkei business daily reported.

TEPCO, which was effectively nationalised by a huge injection of public cash to help it survive the vast costs of the clean-up at Fukushima, has already notified its main lenders about the plans, the newspaper said.

The firm, which has long enjoyed a monopoly in the area it serves, which includes Tokyo, will make the plan part of a comprehensive business strategy to be revised before the end of this year, Nikkei said.

The firm also wants to create an in-house unit handling the aftermath of the Fukushima nuclear plant accident, including cleaning up radiation and decommissioning the crippled reactors, it said.

TEPCO has been struggling to sort out the mess at the plant where reactors melted down in the aftermath of an enormous tsunami in March 2011.

Its efforts there have been criticised as haphazard and disorganised and the firm has been accused of cutting corners.

Critics point out that there is an inherent contradiction in a for-profit company organising and paying for the costly and difficult clean-up and decommissioning.

Deregulation of the tightly-wound power market is one of the planks of a package of reforms that Prime Minister Shinzo Abe's government would like to push through.

His ruling coalition is trying to pass a bill to revise Japan's electricity utilities industry act, which currently does not allow major power providers to spin off business segments.

A TEPCO spokesman denied the news report, saying: "We are trying to clarify our system of command, but we have not decided on such plans."