The proposed closure of an aluminium manufacturing plant in Cumbria could have a severe impact on the local economy, the county council warns.
Unions are being consulted about the proposals
Alcan plans to move production to France from its Pechiney Aviatube site in Lillyhall, Workington, with the possible loss of 161 jobs.
The company says the move is necessary to ensure its long-term viability.
Cumbria County Council says it will negotiate for a support package to retrain affected workers.
Councillor Timothy Heslop, cabinet member for economic strategy, said: "This is an enormously sad time for workers and their families and the thoughts of everyone in Cumbria are with them.
"Our immediate concern is to begin negotiations with the company to arrange a support package to retrain the workforce for opportunities in other industries.
"I understand the company has been manufacturing wing stringer parts for the Airbus programme, which has also experienced difficulties.
"The workforce is highly skilled and competent, and this closure has no reflection on their performance - it's a question of economics."
The Alcan site at Midsomer Norton in Somerset also faces closure, with the possible loss of 218 jobs.