A Spark spokesperson told iTWire: "We are working through the vendor selection process for our 5G network build.

"Late last year GCSB turned down Spark's application to use Huawei equipment as part of that network and we are still working through what possible mitigations we might be able to provide to address the concerns raised by the GCSB and have not yet made any decision on whether or when we should submit a revised proposal to GCSB."

Last year, New Zealand's General Communications Security Bureau, the country's main spy agency, said it had refused Spark permission to use Huawei equipment in its 5G network shortly after the two companies demonstrated the technical implementation of access and core separation for 5G.

New Zealand has continued to insist that Huawei is not banned from participation in the network rollout, with Prime Minister Jacinda Ardern stating in February and again in April that Wellington would make its own decision on use of the Chinese firm's equipment.

Spark told iTWire in April that it had not decided whether to submit a revised proposal to GSCB to see if it could use Huawei gear.

For more than two years, the US has been pushing countries it considers allies to avoid using equipment from Chinese companies, Huawei foremost, in 5G networks. But Washington has produced no proof to back up its claims that these products could be used to spy for China.

Australia imposed a ban on Huawei in August last year while Japan has said it would do likewise.

China is New Zealand's biggest trading partner, with exports worth NZ$15.3 billion to Beijing and imports of NZ$11.9 billion in 2018.