The Ministry of Agriculture and Forestry says it cannot say conclusively yet whether imported pollen is infected with the kiwifruit vine-killing disease PSA.
Kiwifruit marketer Zespri says the first tests have given preliminary positive results and more results are expected on Wednesday.
The ministry's response manager, David Yard, says the first results indicated some level of bacteria, but the results are inconclusive because the ministry does not know if the bacteria was in local or imported pollen.
He says that's because of possible cross-contamination before the samples were submitted to the laboratory.
Earlier, the ministry's head of biosecurity, Barry O'Neil, said it was tentative about what remained a very confused picture.
He said the ministry held no firm belief the tests were positive because of the state of the pollen itself, as opposed to contamination occurring during sampling or processing.