About 100 jobs are expected to be lost from General Cable's Christchurch manufacturing plant, as the company moves some of its production to factories in Asia.
Managing director Chris Birkett says the company suffered significant losses as a result of the global financial crisis and has to make changes to survive.
Those changes include shifting the production of low value-added cables to South-East Asian factories, and upgrading the Christchurch plant with an investment of $5 million.
Mr Birkett says the company has been affected by shrinking margins on some of its products, and strong competition in the Australian market.
He says there will also be workforce reduction and reform at the Christchurch plant, which currently employs almost 350 people.
General Cable has not said how many jobs will go, but the Engineering Printing and Manufacturing Union says about 100 jobs are expected to be cut. It says it will try to reduce the number of job losses.