A petition signed by thousands and backed by three MPs has been presented to Downing Street with the aim of keeping Wales "nuclear free".

As ministers continue to debate the details of an energy plan which will ease Britain through the impending energy crisis, a delegation were on Tuesday delivering a petition to Number 10 which called for non-nuclear power alternatives for Wales.

Liberal Democrat MPs Lembit Opik and Jenny Willott and Labour's Nia Griffith were presenting the document, along with representatives from Welsh environmental groups.

It called for "safer, cleaner and cheaper technology" than nuclear power and has between 4,000 and 5,000 signatures.

A review of UK energy needs is underway,  headed by energy minister Malcolm Wicks and due to report by the middle of next year.

The prime minister has said renewable energy could fill some but not all of the UK's energy shortfall and it is believed he favours building new nuclear power stations as part of Britain's long-term energy mix.

But Willott said Tony Blair should not "simply impose" a new generation of nuclear power stations in Wales.

The existing Trawsfynydd nuclear plant in Gwynedd is being decommissioned and the Wylfa plant on Anglesey is due to close in 2010.

Willott said the message to government was that "nuclear power is not the answer to Wales' energy needs".

"Nuclear power is hugely expensive, has a terrible environmental legacy, and is a huge security risk," she said.

"There is widespread opposition in Wales to nuclear power. Even the secretary of state for Wales, Peter Hain, is anti-nuclear" the Cardiff MP added.