A bitter dispute over the use of foreign workers on construction projects exploded into a series of wildcat strikes across the UK yesterday, with fears of mass strikes unless the row is resolved.

A decision to bring in hundreds of Italian and Portuguese contractors to work on a new £200m plant at the giant Lindsey Oil Refinery at North Killingholme, North Lincolnshire, sparked protests in Scotland, Wales, Northern Ireland and other parts of England in support of jobs for British workers.

Prime Minister Gordon Brown was told his infamous phrase about creating British jobs for British workers had come back to “haunt him”.

A Labour MP last night launched his own inquiry into whether European laws had been broken by excluding British workers from contracts, while the union at the centre of the dispute announced plans for a huge demonstration in Westminster.

Thousands of workers at sites including power stations and oil refineries took unofficial strike action yesterday and there was speculation the dispute will escalate on Monday and spread “like wildfire” across the country if the deadlock is not broken.

Up to 1,000 demonstrators staged a protest for the third day at the Lindsey Oil Refinery

There were sympathy strikes at Kilroot power station in Carrickfergus, the giant Grangemouth oil refinery in Scotland, the Aberthaw power station near Barry in South Wales, a refinery in Wilton, Teesside, a gas terminal at Milford Haven, West Wales, the Fiddlers Ferry power station near Warrington and other sites.

Around 100 Italian and Portuguese workers are on the North Killingholme site, accommodated in large barges moored in Grimsby docks, and are expected to be joined by 300 more next month.

Cleethorpes MP Shona McIsaac said the decision to hire foreign workers was like a “red rag to a bull” to local unemployed people.

Owners Total said the Irem contract involved no anticipated redundancies from the existing contractor workforce.

Bernard McAuley, of trade union Unite, said: “There is sufficient unemployed, skilled labour wanting the right to work on that site and they are demanding the right to work on that site.”