New Zealand Post says the idea of using more motorbikes to make postal deliveries is not the answer to saving jobs in the sector.
The state-owned enterprise announced last week it will halve deliveries to urban areas to three days a week from July 2015. The rural delivery service will run five days a week.
The company had reviewed it services in response to a 30% decline in posted items since 2006.
The Postal Workers' Union said a five day service for urban New Zealand could be viable if more motorbikes or electric bikes were used, to cut down on the dead time walking between routes.
Union president John Maynard said up to 1000 jobs could be lost if NZ Post's plan goes ahead and a five day urban service would reduce the number. He said his union has written to political parties to outline its proposal.
NZ Post spokesperson John Tulloch said the idea has already been looked at but the problem is with decreasing volumes of post, not dead time between routes.
He said NZ Post will work with the unions as it puts changes in place, which will result in several hundred jobs being lost in the sector.