New Zealand First leader Winston Peters is calling for an inquiry into alleged Chinese spy and National Party MP Dr Jian Yang.

Speaking at a meeting in Dunedin on Thursday Mr Peters accused Mr Yang of being a security threat, and working to subvert New Zealand.

"The influence of the Government of China is real within the New Zealand government," Mr Peters says.

"New Zealand became vulnerable the moment National recruited list MP Jian Yang. His decade of work with Chinese military intelligence has only now been opened up, but not yet laid bare."

Dr Yang came under scrutiny after Newsroom alleged he had studied and taught at a spy school before moving to New Zealand.

He denied ever being a spy and denied ever having intelligence training, but admitted teaching students English to help them with their spying activities.

"If you define those cadets as spies then I was teaching spies yes," he said.

Mr Peters is accusing Dr Yang of being part of a communist takeover of NZ.