He revealed in August that the Government wanted the return of a person to face trial. That person was not a Chinese national.
Yesterday Mr Key said the suspect was accused of killing another person.
"It's a long and complicated case."
Mr Key said there had been no deportations of Chinese suspected of fleeing to New Zealand with the proceeds of corruption, although background work had been done on the issue, and it was raised during the official visit of President Xi to New Zealand a year ago.
Mr Key said he would raise at the meeting the issues of China's territorial disputes (with Vietnam, the Philippines, Malaysia, Taiwan and Brunei) in the South China Sea.
China has recently expanded atolls through reclamation in the Spratly group and built airfields.
"We will be doing and making the same consistent comments that we make which is we don't arbitrate with these issues," said Mr Key. "We don't pick sides but it is a very important passage of waterway to us and we do want to see a peaceful resolution to the issue.
"To a certain extent it is the elephant in the room. It is there and the reclamations have been fairly significant, so it is raising the temperature on that issue."
The Vietnamese Prime Minister had raised the issue when Mr Key had talks with him in Hanoi on Monday.
Mr Key laughed off a newspaper article on the English language newspaper Viet Nam News in which he was described in a photo as the president of the Senate of the Czech Republic, Milan Stech.
"It is all part of my global master-plan to increase my sphere of influence and make you all believe I have so many more people under my control."