Fonterra has downsized its milk solids collection forecast following challenging growing conditions and varied weather.
Its opening forecast for the 2021-22 milk collections was 1525 million kilograms of milk solids.
Fonterra confirmed it has revised that forecast to 1500 million kilograms, down 1.6 percent from the initial prediction.
Chief executive Miles Hurrell said actual milk collections were down on the same time last year following differing conditions across many parts of the country.
"We were expecting conditions to improve over the Christmas-New Year period, but this has not eventuated."
At this stage, there was no change was needed to the volume of product the co-op was offering the Global Dairy Trade platform, Hurrell said.
"Due to the high demand for off-Global Dairy Trade sales, we had already reduced the volume we were offering on the Global Dairy Trade platform earlier in the season."
Fonterra would continue to monitor the situation and carefully manage sales both on and off the platform, he said.
This story has been updated to correct an earlier version that suggested Fonterra was reducing its farmgate milk price forecast.