The government might stay involved in the management of Tokyo Electric longer than planned, given the ballooning costs of scrapping the Fukushima No. 1 nuclear power plant, sources close to the matter said.

The delay in reactivating the Kashiwazaki-Kariwa nuclear plant in Niigata Prefecture, the main pillar of the utility's reconstruction plan, is another factor prompting the government rethink, the sources said Saturday. It had planned to end state control next April.

The government is leading the business operations of struggling Tokyo Electric Power Co. Holdings, which is facing huge compensation payments and other problems from the 2011 Fukushima nuclear disaster, because it has acquired 50.1 percent of the firm's voting rights via the state-backed Nuclear Damage Compensation and Decommissioning Facilitation Corp.