Electricity giant British Energy is to close its Scottish headquarters with the loss of up to 80 jobs.
British Energy has been struggling with debt
A further 150 posts at the company's Peel Park office complex in East Kilbride will be transferred to its premises in Barnwood, Gloucester.
The move follows British Energy's June announcement that it was undergoing a major financial restructuring.
The firm confirmed that the headquarters would be "restructured" as a result of the company changing from an international to a UK electricity generator.
However, the company insisted its head office would still be based in Scotland, but at smaller premises.
Managers are set to begin "a process of consultation" with staff and union representatives over the job losses.
A British Energy spokesman said: "British Energy is developing programmes to underpin the long-term viability of the company.
The Scottish Executive is very keen to work with the company to identify a suitable location for its new corporate headquarters - ideally in or close to the East Kilbride area where many of the staff have homes
"As part of its drive for enhanced operational effectiveness and reduced costs, the company has concluded that it can no longer maintain two large office complexes."
British Energy's chairman, chief executive and other corporate directors are expected to still be based in the new Scottish base along with finance, legal and human resources staff.
More than 1,000 of British Energy's 5,091 staff will continue to be based in Scotland, including those at the Hunterston and Torness nuclear plants.
Enterprise Minister Jim Wallace said he was glad British Energy would still be based in Scotland, but "disappointed" that Peel Park was to close.
Mr Wallace also vowed to keep in touch with Scottish Secretary Alistair Darling about the situation.
He added: "The Scottish Executive is very keen to work with the company to identify a suitable location for its new corporate headquarters - ideally in or close to the East Kilbride area where many of the staff have homes."