Key Points:

Auckland's longest serving civic leader has booked an unbudgeted business class trip to China as the council reviews its much criticised overseas travel policy.

Deputy Mayor Dr Bruce Hucker is visiting Guangzhou, China in March to foster the relationship with Auckland's sister city and attend a four-day international conference in a "education and tourism" mission.

The Chinese trip is Hucker's fifth international journey since being re-elected in October 2004. He's been to Japan, Scotland, and Australia twice.

Another senior councillor Scott Milne, who went with Hucker to Glasgow in October, suggested the Guangzhou trip be postponed until a set of key performance indicators, projected outcomes and a budget was set.

Auckland Mayor Dick Hubbard was unaware of the trip until contacted by the Herald on Sunday.

"I'm not up with the play on that one. I can't comment on that," he said.

In April, Hubbard was also unaware of a round-the-world trip by two councillors and two staffers which cost ratepayers more than $85,000.

The month-long business class jaunt by councillors Penny Sefuiva and Vern Walsh and two officers put the spotlight on the council's overseas travel policy. Five months after the trip a 14-page report was produced - essentially, it cost more than $6000 per page.

It was revealed that council rules were changed to allow councillors to plan and approve their own overseas trips, including business class airfares on journeys longer than seven hours.

Hucker defended the trip to Guangzhou and said a detailed budget would be reported at the next committee meeting in February.

He said the four-day "educational mission" would open doors for New Zealand tertiary institutions which have experienced a drop in the numbers of fee-paying Chinese students.

"It's of a major potential benefit to Auckland. Just as large businesses participate in international marketplaces and travel, so too do people from the Auckland City Council. That's a simple idea."