(Repeats to widen distribution)

LONDON, Jan 10 (Reuters) - Britain gave the go-ahead to a new generation of nuclear power stations on Thursday, setting no limits on nuclear expansion and adding momentum to atomic energy’s worldwide renaissance.

The ruling Labour government considered nuclear power unattractive as recently as 2003 but now says it will help Britain meet its climate change goals and avoid overdependence on imported energy amid dwindling North Sea supplies.

Nuclear power stations provide about 18 percent of Britain’s electricity now, but many are nearing the end of their lives.

Energy Secretary John Hutton said the evidence in support of new nuclear stations was compelling and he would not set a limit on the construction of new plants.

“I therefore invite energy companies to bring forward plans to build and operate new nuclear power stations,” he told parliament.

Nuclear operators welcomed the move and announced plans for at least four new reactors. British Energy BGY.L, which already runs eight UK reactors, said it was "positioned to move quite rapidly" to get plants running by late 2017.

Environmental group Greenpeace, which succeeded in blocking an earlier pro-nuclear decision, said the public had been misled during recent consultations and its lawyers were already considering a fresh challenge.

“This is bad news for Britain’s energy security and bad news for our efforts to beat climate change,” Greenpeace Executive Director John Sauven said, adding that government plans to store highly radioactive waste underground were not safe.

RENAISSANCE

Nuclear power is on the verge of a renaissance, having remained unchanged at 16 percent of the global mix for the last 20 years, when the Chernobyl disaster curbed its growth.

It is now becoming more competitive amid surging prices for oil and gas and buoyed by the need to cut carbon emissions to fight climate change.

Already, countries such as France and Finland are building new nuclear plants and, in the United States, companies have begun filing licence applications, reinforcing the view atomic energy is part of the solution to the world’s energy problems.

Irish energy minister Eamon Ryan called on Thursday for a public debate on whether to reverse a ban on nuclear power in Ireland, which depends on fuel imports and is situated at the very end of Europe’s gas network.

There is opposition to nuclear among some states, however, including Germany, an anti-nuclear stronghold. Critics say the toxic waste from nuclear power generation remains a problem for thousands of years and is not worth the risk.

Hutton said the UK would not subsidise any new reactors, but the government would step in to help in case of a catastrophe.

Britain’s opposition Conservative Party lent its support to the decision and vowed to “set aside political scrapping”, but London Mayor Ken Livingstone called the decision “the mistake of a generation”.

GLOBAL COMPETITION

Nuclear operators say they could have new plants running in Britain by 2017, but analysts point to tough global competition for components and experienced nuclear workers.

“The UK will need to work hard to remain an attractive option,” said Tony Ward of Ernst & Young, adding that more than 30 reactors were under construction around the world, and over 90 were in the pipeline.

Hutton said he expected several new plants to be running by the mid-2020s and France's EDF EDF.PA said it aimed to build four reactors in the UK.

Britain's Centrica CNA.L, France's Areva CEPFi.PA and Germany's RWE RWEG.DE and E.ON EONG.DE also said they were keen to get involved.

The government green light was accompanied by publication of an Energy Bill to be fast-tracked through parliament with the Climate Change Bill and the Planning Bill.

Hutton said the government would give more support to wind, wave and tidal energy.

The trio of bills form the backbone of the government’s new energy and climate policy for the next decades.

To read more on the UK nuclear decision, click on: [nL10586261] Have your say on nuclear power: here (Additional reporting by Adrian Croft, Katherine Baldwin and Jonathan Saul; Editing by Michael Winfrey)