SHARES in Toshiba have gone into freefall again, casting fresh doubts about Cumbria's nuclear new build.

The value of the Japanese company - which is key mover behind a proposed new power plant at Moorside, near Sellafield - has fallen by 16 per cent after it was reported it might have to announce a larger-than-predicted $6bn (about £4.8bn) writedown for its American nuclear business.

Last month the company announced its US subsidiary, Westinghouse Electric, may have overpaid by several billions of dollars for another nuclear construction and services business. The size of the writedown was predicted to be between $1bn-$4.5bn.

Following the reports its shares fell to 242.3 yen (£1.71).

To compound matters, the company is embroiled in an accounting scandal and there are unconfirmed reports that it has applied for aid from the Development Bank of Japan, which is backed by the country's government.

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

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

NuGen has said it "remains committed" to plans for a nuclear power station in Cumbria, despite the crisis affecting Toshiba.

A spokesman said: "NuGen’s shareholders [Toshiba and ENGIE] remain committed to the development of our Moorside project.

"NuGen is actively engaged in exploring a universe of investment opportunities to bring in additional investments, including debt and equity, to help fund the construction of Europe’s largest new nuclear power station."

He added: "NuGen welcomed the recent signing of a memorandum of cooperation between the UK and Japanese governments.

"The agreement shows confidence in the progress and deliverability of Moorside and commitment to nuclear as a solution to meeting the UK’s low carbon electricity requirements.”

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.