Labour is demanding assurance from the Government that steel used in the SkyCity Convention Centre steel will be up to scratch.
Half of all the steel that will go into Auckland's controversial new convention centre at SkyCity will come via a United States-owned company in Thailand.
Labour leader Andrew Little says there are big problems with quality control when importing the metal.
"Steel used in the Huntly bypass project, steel used in the Christchurch reconstruction -- all of those that have come from offshore have suffered quality issues," says Mr Little.
"There just seems to be something severely wrong with our quality assurance processes. I would rather trust local suppliers and local businesses to do the job and at the same time keep Kiwis in work."
Mr Little says sourcing the steel locally would have been safer and provided jobs.
"There are firms that have geared up in the expectation that they're going to get to work, and now they're not going to," says Mr Little. "They're going to be struggling to get out of work to fill that gap."
Kiwi manufacturers are also unhappy that work has being taken away from them, but also that there's no guarantee Chinese steel will be good enough.
Joe Gallagher from union E Tu says there are no tariffs to ensure imported steel is up to standard.
"We don't seem to have a clear quality-control process in place, and they're allowed to bring in these low-quality products when we have a perfectly steel mill in New Zealand that could provide high-quality product," says Mr Gallagher.
Mr Gallagher says local manufacturers had been told to gear up for the project and feel they have been misled.
Last week imported steel from China was found to be too weak for bridges on the new $450 million Huntly bypass.