Labour list MP Maryan Street says the 180 people facing redundancy at the Sealord processing plant in Nelson will struggle to find other jobs.
A union rally was held in Nelson's Trafalgar Street on Saturday to demonstrate support for the workers.
Ms Street said Work & Income has only 140 jobs available throughout Nelson, Tasman, Marlborough and the West Coast.
She called on Sealord to suspend its decision and recommence talks with the Service & Food Workers Union over the restructuring, which is due to take place next month.
An international union leader says the Sealord company's move to axe workers is another example of jobs being dumped in the name of enhanced profits.
Ron Oswald, the Geneva-based general secretary of the Food Workers Union, addressed the 150 people who marched in support of Sealord workers.
The marchers say Sealord's planned redundancies are not due to the recession, but to a profit-based restructure.
Sealord says the processing plant is not viable.