WILDCAT strikes are expected to spread today in an escalation of the row over foreign labour ahead of frantic moves to try to resolve the increasingly bitter dispute.

Hundreds of contract workers at the Sellafield nuclear site in Cumbria were holding an early morning mass meeting to discuss taking industrial action.

Contractors at the Heysham nuclear power station in Lancashire are also expected to decide whether to join the unofficial walk-outs in support of workers at the Total oil refinery in Lincolnshire, where the dispute started.

Bosses from Total were meeting sub contractors and union leaders in hastily-arranged talks in Scunthorpe.

Moves are also under way to set up a special panel, under an independent chairman, to review the recruitment of hundreds of Italian and Portuguese workers on the £200 million plant at the giant Lindsey Oil Refinery at North Killingholme, North Lincolnshire. Unions claim Britons were not given any opportunity to apply for the posts.

The Prime Minister has now been drawn into the dispute and was accused of “inflaming” the row today after he condemned the outbreak of wild-cat strikes as “indefensible”.

Paul Kenny, general secretary of the GMB union urged the Government to do more to resolve the row rather than “blame” British workers.

Gordon Brown came under attack after he criticised the unofficial strikes that were held at up to 20 construction sites at the end of last week, involving thousands of workers.

Business Secretary Lord Mandelson also stepped into the dispute when he warned that protectionism would be a “sure fire” way of turning the recession into a depression.

Mr Kenny accused the Prime Minister and Lord Mandelson of inflaming the situation adding: “We should be doing everything we can to look for a solution rather than blaming the workers.”

Lord Mandelson held a private meeting at the weekend in London with Derek Simpson, joint leader of Unite, one of the unions at the centre of the dispute.

Energy Secretary Ed Miliband was also at the meeting, held to try to find a breakthrough in the deadlocked row.