A dispute involving hundreds of workers who were sacked last week at the Lindsey oil refinery has been settled.

An agreement was finally reached after long talks between union leaders and the employers of contract staff at the north Lincolnshire plant and will be put to workers on Monday.

The deal is understood to involve the reinstatement of the 647 construction workers sacked by a subcontractor at the plant after they took unofficial industrial action after learning that 51 of their colleagues were set to lose their jobs. It is thought that the agreement will mean that those whose jobs were initially at risk will be offered new roles.

Unions have also won assurances that thousands of contract workers at power plants, refineries and gas terminals across Britain who also walked out in sympathy will not be victimised for their actions.

Les Bayliss of Unite, the trade union, said: “Following hours of detailed negotiations, we now have proposals for a return to work that the unions will put to the members at Lindsey.

“Employers have agreed reinstatement of sacked workers. The details will be put to the workforce on Monday morning.”

The GMB union said that it would recommend workers accept the deal and call off the unofficial strike.

Total, the French energy group that owns Lindsey, said it was pleased that the contract companies and unions were able to reach a positive conclusion and that it expected contractors to be able to return to work as soon as possible and complete the desulphurisation unit on which they were working on time.

While production at the plant had not been affected by the strike, the company said stoppages on the construction project had cost it €100 million (£85 million).

The settlement brings to an end the second big row at the plant, one of Britain’s largest oil refineries, this year after mass industrial action in January over the use of foreign workers.

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