SHARES in Toshiba, the prime mover behind plans for a nuclear power station in west Cumbria, have gone into freefall.

Forty per cent has been wiped off the Japanese company's value after it said last week that its US subsidiary, Westinghouse Electric, may have overpaid by several billions of dollars for another nuclear construction and services business.

To compound matters, the company is embroiled in an accounting scandal.

Its shares plunged to 259 yen (£1.81) on Thursday before staging a modest recovery on Friday.

It is not clear what, if any, impact the crisis will have on plans for a £10bn nuclear power station at Moorside, Sellafield.

However, the agency Moody's has downgraded Toshiba's ratings and warned that the writedown could affect the company's ability to pay its debts.

Toshiba holds a 60 per cent stake in Moorside developer NuGen, alongside ENGIE of France. A decision on whether to proceed with the project is due in 2018.

NuGen has been seeking further backers for the scheme and is understood to have held talks about potential investment from the Korea Electrical Power Corporation.

If Moorside does go ahead, Westinghouse, which was once owned by British Nuclear Fuels, would supply three of its AP1000 reactors.

When fully operational, they would have a combined capacity of up to 3.8GW, enough to power 6m homes and supply 7.5 per cent of the UK's electricity needs.

The first is due to come online in the mid-2020s.