Prime Minister John Key says the loss of up to 2000 postal jobs is the "brutal reality" of people sending fewer letters.
New Zealand Post announced yesterday that it expected to axe the jobs in an attempt to safeguard its future options.
Chairman Sir Michael Cullen said the organisation would focus on logistics and financial services, innovation in its mail and retail network, and lowering costs.
The changes, which have been slammed as "simply cruel" by the posties' union, will start to be implemented next year.
Mr Key acknowledged it was a difficult time for everyone involved, but said it was the "brutal reality" of people sending fewer letters.
"Unfortunately, technology is dramatically changing the way we communicate with each other ... at the same time we're seeing an increase in jobs in the IT space.
"It's a change that not just New Zealand but a lot of other countries are going through."
Mr Key disagreed with the union that the Government had made the announcement "out of the blue".
"There's been a lot of discussion about what would happen if there was a change to the number of days that the mail was delivered to people's homes.
"Overall, I think this has been well and truly telegraphed."
Engineering, Printing and Manufacturing Union postal industry organiser Joe Gallagher said the announcement had come as a shock to members
"Yet again New Zealand Post and the Government have made a huge announcement out of the blue.
"These plans have clearly been in the pipeline for a long time, but the people affected by them, including all New Zealanders who use the postal service, have been kept in the dark."
The company's plans include:
• Giving customers the choice of a priority overnight delivery and non-priority service.
• Getting posties off bikes and into vehicles.
• Closing specialist Post Shops and putting them in another business.
• Post will now be delivered at least three days a week in towns and cities and five days a week for rural addresses. There will still be a "premium service" six days a week.