Blood was certainly thicker than water when this three-month-old white tiger cub had to be rescued by his brothers after tumbling into water at a Japanese zoo.

The male quadruplets were making their debut public appearance in glass cages at Tobu Zoo in the outskirts of Tokyo.

Born on 25 January, the cubs were initially reluctant to go out in front of a crowd of zoo staff and visitors, but, encouraged by their mother, they did and, curiosity getting the better of them, they started playing near the water.

Then trouble struck: one accidentally fell into the play pool, and his brothers ran to the rescue.

"We can hear it from beyond this glass wall, it must be screaming really loudly. I wonder if the parent will come to the rescue? Ah they made it!" someone can be heard on footage released by the zoo.

Zoo spokesman Naoteru Yamaguchi said, while he could not read a tiger's mind, he is convinced they had witnessed brotherly love.

Currently, the cubs are not named and the zoo will be taking suggestions from the public in May. They will be permanently based in the glass cage from 22 April.