Fonterra is still determining the extent of damage to a storage facility at its Pahiatua milk processing plant following a strong earthquake in the lower North Island on Monday.
The 6.2-magnitude quake hit 15km east of Eketahuna in the Tararua District.
The plant has stopped taking milk while structural checks are carried out.
The dairy co-operative says it is still collecting milk from throughout the region and diverting it to other plants in the meantime.
Operations manager Robert Spurway says the plant will resume processing as soon as the checks are finished and any repair work is done.
The Pahiatua plant processes about 1.4 million litres of milk a day.