Wildcat strikes over foreign labour have spread with around 900 contract workers at the Sellafield nuclear site joining the protest.

Industrial action at the Cumbrian site is expected to be followed by a series of walkouts across the country in the escalating row over the hiring of Italian and Portuguese workers on a power station project.

More than 300 contractors have walked out at Heysham nuclear power station in Lancashire and a similar number have taken action at Fiddler's Ferry power station in Widnes.

The atrocious weather could affect the number of workers joining the action, but union sources said they expected widespread action as feeling were running high.

Business Secretary Lord Mandelson maintained that UK firms and workers were not being discriminated against and called for the unofficial strikes to stop.

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