An academic is concerned New Zealand's relationship with China could suffer after the GCSB decided Spark couldn't use Chinese equipment for its 5G network.
The GCSB says using Huawei hardware would raise a significant security risk.
Victoria University strategic studies professor, Robert Ayson, told Mike Hosking it is a bold move.
"I think it's an important sign that New Zealand's approach to China is becoming more cautious. I think the special friendship between New Zealand and China is now a little less special in some ways.
He said it's a change in approach by New Zealand in how it's dealing with China.
"This is really going to be the further sign of New Zealand getting more concerned about China's activities including the activities of companies associated with China."
Ayson said the decision would have been based partly on security concerns and partly on the issues it could raise with the Five Eyes intelligence alliance.
"I think quite a few people will be reading this as New Zealand sitting in with the preferences of key partners Australia and the United States who have concerns."
"In a Five Eyes context, I guess one of the question is, does New Zealand want to be seen as a weaker link?"
The GCSB's apparent move comes after reports on Friday that the US was pressuring allies to drop Huawei.