Wedlock said the tourism industry had not done enough to support Jetstar's service.
"It's a use it or lose it scenario. We can work hard to gain it [a service] but if the industry doesn't support it, particularly in the early years, then it's going to disappear."
Tourism operators who benefited from more capacity needed to spend more on marketing when new routes were started.
Jetstar started flying daily Singapore-Auckland services in March 2011, but this was later reduced to three times a week.
A spokesman said: "The route was reviewed as part of ongoing business and the decision made based on past performance and future potential. It is clear that there are challenges that Jetstar is facing with increased competition from a number of carriers across its network."
Capacity could be put to better use on other routes, he said.
Jetstar is part of the troubled Qantas group but in the next few months it is starting long-haul services between Melbourne and Tokyo Narita and between Brisbane and Bali.