jacinda arden and xi
© RAO AIMIN/XINHUA/ALAMYJacinda Ardern in Beijing with President Xi last month
New Zealand has broken away from its western intelligence allies with an offer to support China's contentious global infrastructure and investment project.

The Belt and Road initiative involves Chinese state banks offering funds to develop transport schemes around the world to facilitate trade.

Supporters present it as a development initiative but critics say it is primarily to advance Beijing's strategic interests, and even a form of "debt colonialisation". Beijing has recently tried to recast the programme, promising to improve standards and transparency.

Jacinda Ardern, the New Zealand prime minister, said she believed the scheme had "really evolved" and her government was prepared to offer Beijing advice on expanding it. Her trade minister, David Parker, said that New Zealand believed that it could "find a win-win situation with China".

The shift overrides the reservations of Winston Peters, Ms Ardern's foreign minister, and follows concerns about the encroachment of Chinese technology into the Five Eyes intelligence network, which comprises New Zealand, the UK, the US, Canada and Australia.

New Zealand has traditionally had friendly relations with China, signing a free-trade agreement in 2008, the first signed by Beijing with a developed country.

China is New Zealand's second largest trading partner and prime market for its dairy exports. It recently became the first western nation to join the Chinese-inspired Asian Infrastructure Investment Bank, which is seen by some as a rival to the IMF and the World Bank.

The G7 countries - the US, Canada, Britain, France, Germany, Italy and Japan - have questioned the transparency and intentions behind China's initiative, but in March Italy became the first member of the group to sign up.

"The fact that we've taken a little bit of a pause as we've worked to really flesh out that arrangement has been no bad thing because Belt and Road has really evolved," Ms Ardern told a business conference.

Mr Parker said New Zealand could offer expert advice on regulation, transparency and environmental issues. The country has criticised some of China's lending to the Pacific region, and has refused to allow Huawei, the Chinese technology company, to take part in its 5G data network.