New Zealand First leader Winston Peters has warned that planned Foreign Affairs job losses and the closure of overseas posts will cost more in the long run than they save.
It was announced last year in a State Services Commission report that the ministry was looking at slashing 200 jobs out of almost 1000 at the ministry.
An announcement on details is expected soon.
Mr Peters, a former minister of foreign affairs who negotiated a big increase in funding for the portfolio, said a "slash and burn exercise" would seriously affect this country's overseas trade.
He said the move was a "serious, retrograde step" at a time New Zealand was desperately trying to increase its export trade.
"At a time when our interests need to be seriously promoted and defended, this cost cutting exercise under the disguise of 'greater efficiencies and high quality services' is devoid of substance and reason.
"If you compare New Zealand's overseas presence with Singapore and Norway, two similar sized countries, you will see that we have less than forty per cent of their international effort," he said.
"This tinkering with our international interests and nonsense about setting up offices based on a hub with spokes will seriously harm our reputation and our trade."
Conservative estimates puts the size state sector at 1702 positions fewer than when National came to office as it has moved to cap and then cut the number of state workers.
That has seen the public sector shrink from 45,297 in December 2008 to 43,595.
Some of the deepest cuts since 2008 (including losses forecast to June 2013) are at Housing New Zealand (70 - 200), Agriculture and Forestry (241), Conservation (124), Defence (188), Inland Revenue (156), and Foreign Affairs
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