The Council of Trade Unions says workers soon to be made redundant by Telecom will struggle to find employment in New Zealand.
Telecom on Friday downgraded its profit forecast and announced it would cut hundreds of jobs in the coming months as it made a strategic shift to become a mobile and data orientated service provider.
CTU secretary Peter Conway said the redundant workers will be highly skilled and many will be unable to find equivalent jobs in New Zealand's faltering economy.
He said any growth in the New Zealand economy is highly concentrated in some sectors and is either not leading to extra jobs or, where jobs are created, they are not very good ones. "That's the concern and that will keep driving people to Australia."
The Engineering, Printing and Manufacturing Union represents about 40 Telecom workers. National industry organiser Joe Gallagher said those who lose their jobs will probably have to leave the country to find employment.
Telecom's announcement follows recent job losses at Mainzeal, Summit Wool Spinners and Contact Energy.
The Household Labour Force survey for the December 2012 quarter puts the number of unemployed at 163,000 and Mr Conway said 111,000 part-time employees are looking for extra hours.
In Australia, telecommunications firm Telstra announced this week it was cutting jobs and and moving some of them overseas.
The company is axing 648 jobs axed from its ailing advertising and directories arm, Sensis, representing almost 20% of its 3500-strong workforce.
The Australian Manufacturing Workers Union said 400 of those jobs are earmarked to go to workers in the Philippines, AAP reports.