When an Air New Zealand jet to Shanghai was forced to turn around earlier this month, it seemed a relatively innocuous event put down to misfiled paperwork.

But it was the first of a string of incidents that are fueling concerns China may be turning a cold shoulder toward New Zealand after it barred Huawei Technologies Co. from its next-generation wireless networks. While Prime Minister Jacinda Ardern denies any friction, the opposition is calling on her government to shore up the relationship to avoid potentially dire economic consequences.

¡°Our relationship with China is worth over NZ$27 billion in two-way trade,¡± opposition National Party foreign affairs spokesman Todd McClay wrote in a New Zealand Herald column on Sunday. ¡°The prospect of a deteriorating relationship with China is a major risk. It hampers certainty in the economy and creates uncertainty for our exporters and tourism operators.¡±