Former prime minister John Key has described the visit to Taiwan by US house speaker Nancy Pelosi as reckless, provocative and dangerous.
Taiwan's defence ministry said China had retaliated by simulating an attack on the country with military exercises unprecedented in scale.
Key told TVNZ's Q and A programme this morning that for the third most important elected official in the US to turn up on Taiwanese territory is poking the bear.
"You have to say well why is Nancy Pelosi doing that and why is she doing that at the end of her political career," he said.
"And the answer is because she wants to make a personal stand, I understand that, but at what cost. That's already putting enormous tension and increased tension on the Taiwan straits."
Key said he believed it was extremely unlikely China would invade Taiwan in the short term.