A litter of rare lion cubs were born at the Toronto Zoo over the weekend.

One of the zoo's female white lions, named Makali, gave birth to four cubs, the zoo announced in a statement on Friday.

Two of the cubs were born on Saturday, Sept. 26 and another two were born on Sunday, Sept. 27. All four cubs appear to be healthy and are feeding well.

However, the zoo warned that the first 30 days will be critical for the cubs, each approximately the size of a small house cat. The babies will be monitored closely by zoo staff for the first month.

The cubs and their mother are living in the maternity area of the lion habitat, and are not currently visible to the public. The zoo posted a video of the cubs online on Friday so fans of the creatures can view the cubs and their mother.

In the statement, the zoo said Makali first showed signs of pregnancy two weeks ago, and zoo staff began to monitor the giant cat 24 hours a day.

Makali and Fintan, the cubs' father, are both four years old. The cubs are the pair's first litter.

White lions are found in the wild in an area spanning from the Sahara Desert to South Africa. They are listed as vulnerable on the International Union for Conservation of Nature (IUCN) list of threatened species.

There has been a decline of between 30 and 50 per cent of wild lion populations in the last 20 years. The large cats are threatened by hunters and disease.

The Toronto Zoo supports conservation efforts in Africa through its Endangered Species Reserve Fund.