National leader Simon Bridges is rejecting the claim he met with the head of China's "secret police", saying that is an "unfair characterisation" of the man he met.

Bridges was back in Wellington on Tuesday following his five-day visit to the superpower, where he met with Guo Shengkun who is responsible for the Ministry of State Security (MSS).

MSS is China's intelligence and security agency. The US Department of Justice has described it as being like a combination of the CIA and FBI.

Canterbury University Professor Anne-Marie Brady, an expert on Chinese politics, tweeted about Bridges' meeting on Sunday, describing Shengkun as "in charge of China's secret police".