The Hong Kong Breast Milk Bank has begun serving premature or critically-ill newborns across the city, just two months after it came into operation in January.

The city's first milk bank, located at the Children's Hospital in Kai Tak, has so far recruited more than 100 eligible donors and collected more than 300 litres of milk.

Paediatrician Rosanna Wong, the milk bank's director, said the numbers were "more than expected".

She revealed the bank began distributing donor milk to the city's nine public neonatal intensive care units starting this month.

Priority is currently given to babies born under 32 weeks of gestation, or weigh less than 1.5kg.

"Other babies who require the milk will be those who have severe diseases like congenital heart disease, or after a gastrointestinal operation," she added.

Wong called for additional donations from lactating mothers, saying they could help the bank extend its free service to less premature babies or full-term infants with special needs.