Britain is braced for more wildcat strikes after a day of confusion in the Government that failed to resolve the row over foreign workers.

Up to 1,000 construction workers at Sellafield, the nuclear reprocessing facility, will decide today whether to join the walkout over building jobs, which unions claim are being handed straight to overseas workers.

Ministers were forced into an embarrassing U-turn yesterday after Alan Johnson, the Health Secretary, suggested that the Government was preparing to bow to union demands to push for measures in Europe to protect British jobs. Unions want a new EU directive to overturn a ruling by the European Court of Justice in 2007 that made it easier for companies to circumvent pay deals by hiring foreigners on lower wages. They believe that Gordon Brown could be forced to take action after promising “British jobs for British workers” in his 2007 Labour conference speech.

Mr Johnson, a former union leader, said: “We need to bring in fresh directives to make it absolutely clear that people cannot be undercut in this way.” This was firmly rebuffed, however, by Lord Mandelson, the Business Secretary, who said that it would be a huge mistake. He questioned the influence of the court rulings, saying that they were generating debate among lawyers.

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Total, which runs the Lindsey oil refinery where the dispute began, issued a statement later hinting that it may offer jobs to Britons alongside the Italians and Portuguese workers who have been hired for construction jobs. “It is legal for subcontractors to supply their own employees but, where vacancies are advertised, we will work with our subcontractors to ensure that British workers are considered in the same way as anyone else,” it said.

After the statement, Lord Mandelson urged workers to call off the industrial action. He appeared to side with Total to insist that the subcontractors were operating within the law. “The law is not being broken and it will not be broken and I hope this message is now carried across all those workforces that have been understand-ably concerned.”

Acas, the conciliation service, will meet unions, workers and employers today to find a way to halt the strikes and protests, which spread to more than a dozen locations last week. The unions Unite and the GMB are expected to back the creation of an independent panel to investigate individual complaints by British workers of being excluded from jobs. Unions said that they had warned the Government weeks ago that British workers were being prevented from applying for construction jobs because foreign workers were coming in on less money.

Nervousness about the strikes was fuelled by news that the British National Party was promoting the protests on its website, using the “British jobs for British workers” slogan.

Sadiq Khan, the Communities Minister, said: “What we cannot have is the perception that foreign companies are abusing the rules of the EU to penalise British workers who have the skills to do the job.”

There were also warnings from Peter Hain, the former Cabinet minister, that the dispute could damage Britain’s energy supply. “They could actually stop petrol supplies and stop power supplies,” he said, a claim that was firmly denied by the Department for Energy and Climate Change.

The Times has learnt, however, that National Grid, the power distributor, is monitoring the situation very closely in case electricity and gas supplies are interrupted. The company could instruct large energy users, such as factories, to close because maintaining domestic power supplies is regarded as the top priority, especially as snow and low temperatures grip the country.

The unions stepped up the pressure yesterday, even though they do not formally support the unofficial protest, with plans for a protest march in London on Thursday.

Derek Simpson, the joint general secretary of Unite, called on the Government to use social responsibility rules to force companies that receive public funds to consider hiring British workers. Mr Simpson is battling for reelection to his union post. Other candidates for his job have seized on the issue, including Jerry Hicks, who alleges on his campaign website that he sustained a fractured leg after being assaulted by the police during a protest at Staythorpe power station.

The unions are desperate to overturn two European rulings, known as the Viking and Laval cases, which prevent them from protesting against companies that bring in foreign workers and undercut collective bargaining agreements. The European Council, including Britain, committed itself to the status quo as recently as December 17.

Dialogue diary

Today 700 Sellafield contractors meet to discuss strike action

Today Acas meets both sides to try to resolve walkouts at refineries and power stations

Today and tomorrow Balpa pilots’ union seeks meetings with bmi management over pay freeze amid calls for strike

Wednesday Company bosses and unions in the construction and engineering sector meet to discuss strikes

Wednesday Electricians working for London Underground stage strike

Thursday Union delegation meets MPs and goes to Downing Street to talk about the industrial strife

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