Ministers have promised an urgent inquiry into the award of contracts to foreign firms, in the hope of ending a wave of wildcat strikes across the UK, reminiscent of the 1970s.
Almost 5,000 placard-waving workers demonstrated outside 17 oil refineries, power plants and chemical works, as a dispute that began in Lincolnshire two days earlier spread to Scotland, Wales, Northern Ireland, across the north of England and also the south coast. The protests are scheduled to begin again before dawn on Monday, when an additional 900 contractors at Sellafield nuclear power plant will meet to discuss industrial action.
Whitehall officials were monitoring the situation last night and said contingency plans to prevent disruption to petrol supplies were in place. They insisted that the protests by engineering and construction workers had not affected petrol deliveries.
The strikers want Gordon Brown to make good his promise contained in a speech to the Labour Party conference 16 months ago, when he said there would be "British jobs for British workers".
The long day's industrial action began at 6am, when 800 strikers gathered outside the refinery in North Killingholme, Lincolnshire, where the first dispute broke out on Wednesday. The refinery covers 500 acres and is the third largest in the UK, processing 10 million tonnes of crude oil per year.
Workers there have objected to the award of part of a £100m contract to an Italian firm, IREM, which brought in its own specialist workforce of Italian and Portugese workers. About 100 guest workers are already on site, living in housing barges moored in Grimsby docks. Another 300 are expected to join them in the coming weeks.
The Environment Secretary, Hilary Benn, said yesterday the demonstrators were "entitled to an answer". Pat McFadden, the Employment minister, added: "What I want to do is to establish the facts about some of the allegations that have been going on about sub-contracting at some of these sites."
He called in the conciliation service, Acas, to hold a review that will report to the Government, employers and unions as soon as possible, he said.
What was not clear yesterday is what the Government can do to stop firms employing workers from the EU if they choose to do so. A new points-based immigration system that came into force in Britain in November prevents employers from recruiting abroad if there are suitably qualified resident workers who can do the work – but under EU law, a resident worker means anyone from any EU country.
In Italy yesterday, there was bemusement about why British workers were protesting. "We are sorry about what is happening in England," said Giovanni Musso, the vice-president of IREM, yesterday. But he added: "We won the contract and, as always, we scrupulously followed the local rules and regulations regarding work, the rules imposed by the trade unions and so on. We can't understand what's happening, but it's clear it is connected to the world economic crisis, and can also happen elsewhere."
He said that IREM's share of the work, sub-contracted by a US firm, was worth about £17m, and was due to be complete by April.
Mr McFadden said the Prime Minister had never implied the UK would break EU law. "What he's saying there is 'I want to see the British workforce equipped for the jobs and skills of the future' – and that's precisely what the Government is doing."
Within half an hour of the demonstration beginning in Lincolnshire, strikes were breaking out across the UK. Six plants in Scotland were hit. At the Grangemouth oil refinery in central Scotland, about 800 union members employed by BP and the chemicals company INEOS met and walked out in solidarity with the Lincolnshire strikers.
Roughly 1,000 contractors went on strike at five other sites – Scottish Power's Longannet and Cockenzie power stations, in Fife and East Lothian, Shell's St Fergus gas plant in Aberdeenshire, British Energy's Torness facility in East Lothian and Mossmorran chemical plant in Fife.
Police were called to Aberthaw power station in south Wales at 6.30am, after 50 workers decided to stage a demonstration outside the gates. It lasted for about five hours, without incident. Another 1,000 took part in a strike at the South Hook liquified natural gas terminal in Milford Haven, Pembrokeshire.
Cleveland Police said 400 demonstrators had staged a protest at all four gates of the former ICI complex at Wilton on Teesside, and 200 gathered outside the Corus steel plant near Redcar. Another 300 walked out at the Fiddlers Ferry power station, on the banks of the river Mersey near Widnes, Cheshire. About 60 took part in a strike at Kilroot Power station just outside Larne, Co Antrim, Northern Ireland.
Ministers are hoping the strikers will return to normal work on Monday, but there are already signs that the action could escalate. At the huge Sellafield nuclear complex in Cumbria, 900 workers are planning a meeting in a nearby car park to decide whether to stage a sympathy strike.
David Cameron, the Conservative leader, said: "I completely understand people's anxieties about unemployment and the effect it has on families and their finances. There are legitimate questions to be asked of this company. If it is disqualifying British workers from applying for jobs then that is illegal. But the Prime Minister should never have used that slogan. He has been taking people for fools and has been found out."
Nick Clegg, the Liberal Democrat leader, will use a speech on Monday to warn that the economic crisis could lead to unrest. He will say: "While the economic downturn makes some people turn off politics completely others will turn to extremism."
In a statement yesterday, Total said: "We recognise the concerns of contractors but it is important to note that there will be no direct redundancies as a result of this contract being awarded. We have been a major local employer for 40 years and have always enjoyed a good relationship with our staff and contractors."
Foreign workers: Why British staff are angry
*What is this dispute about?
It centres on work to extend a Total oil refinery in Lincolnshire which was sub-contracted to an Italian firm, IREM, which brought in its own Italian and Portuguese staff to do the job. Union leaders are angry UK-based staff have not been able to apply for the work.
*Have British workers lost their jobs?
Total has insisted no British workers will lose their jobs as a result of the deal to build the desulphurisation plant, and insist the vast majority of 550 permanent staff and up to 1,000 contractors at the refinery are British.
*How many foreign workers are in the UK?
Estimates are controversial. However, figures for the Office for National Statistics show 3.7 million non-British born workers in the country last year. Some 1.4 million of those were born in the European Union.
*Are the strikes legal?
Industrial action must be authorised by a ballot and employers must be given notice of any strike action. Yesterday's wildcat strikes areunofficial action and have not been backed by union leaders.
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