WELLINGTON (AFP) - China is insisting one of the main wastewater pipes beneath the New Zealand capital Wellington be diverted to ease security concerns for its new embassy, a city official confirmed on Thursday (July 7).

The pipe is large enough for people to walk through and runs under a block of land where the new Chinese embassy is to be built.

"Security is the issue," Wellington city council spokesman Richard MacLean said.

"It's a big enough pipe for people to move around in."

The council has no objections to the pipe being moved but has insisted the work be done at China's expense.

"If they want it shifted, they will have to organise it and pay for it and we will oversee the project. That's our bottom line," MacLean said.

"It will be a big project to shift that pipe."

The Chinese ambassador to New Zealand, Wang Xiaolong, told The Dominion Post newspaper that the embassy "was working with the council" on the pipes so the building could proceed.

The Chinese embassy was not immediately able to provide a comment.

China has been targeted by protesters over a number of issues in recent years including its human rights record, the political crackdown in Hong Kong, the treatment of Uyghurs and other Muslim minorities, and heightened tensions with Taiwan.

The Wellington City Council approved resource consent for the new embassy four years ago but there has been no work done on the site.