The complex has suffered three damaging stoppages in a dispute over shift payments.

But now union leaders have said they will call off a planned fourth strike on 5 December so arbitration talks can be held at ACAS.

About 350 members of the GMB and Amicus unions are involved in the stoppage.

Further strike threat

The unions accuse British Nuclear Fuels (BNFL) of reneging on an agreement to close a �2,000 pay gap between white collar and manual workers, a charge the company has denied.

Peter Cane from the GMB union says the decision to suspend the next strike was taken at a meeting of shop stewards on Monday.

But he stressed that a further strike planned for 12th December would still take place if talks with ACAS broke down.

A BNFL spokesman said: "We can confirm that BNFL management has made proposals to the unions to resolve the dispute through arbitration involving Acas."

"Sellafield management is hopeful of a positive response that will allow further talks to get underway."