Total, the French energy group whose Lindsey oil refinery in North Lincolnshire has been hit by wildcat strikes, said that it was “actively encouraging” talks between unions and contract workers.

The workers, who burnt their dismissal letters outside the plant yesterday, are continuing to protest today.

Hundreds of construction contractors at the refinery have refused to work over the past week in a dispute after some workers were told they may lose their jobs on a desulphurisation plant.

The company sacked about 650 workers in response to the unofficial strike action, which has sparked sympathy strikes across the country.

A spokesman for the Unite union said he hoped talks between unions and employers representatives, expected to be held later today, would help hammer out a solution and that he was confident the contractors would return to work. However, the reinstatement of the sacked workers remains a sticking point.

Total said that the dispute has cost €100 million and was jeopardising a key construction project.

“The HDS-3 project is now six months behind schedule and the delays, under performance and low productivity have already cost in the region of an additional €100 million,” Total said. “Further cost overruns will jeopardise the future viability of this important inward investment into the UK.”

Michel Benezit, Total's president of refining and marketing, said that the dispute was out of the company’s hands because it involved sub-contractors. “The work should have been finished by now and the unit should be in operation. Because of poor productivity and disputes, we still have a long way to go," he said.

“I want to make it clear that we have not fired anyone because we have no employees involved in this work. There is not much we can do. My only goal is to see an end to the strike as soon as possible. We have already suffered huge cost over-runs.”

The GMB union has accused Total of provoking the dispute, which was sparked when 51 workers were laid off at the same time as another contractor on the site was hiring staff.

The Lindsey refinery was at the centre of a dispute earlier this year over the use of foreign labour on contract projects.

Elsewhere, workers at the Coryton oil refinery in Essex took action for the first time today since the dispute flared over a week ago, joining strikers from power stations and oil and gas sites.

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