One of the world's rarest tigers has been born at London Zoo, as part of a conservation push to save the critically endangered species.

       Footage from the zoo shows Gaysha, a 10-year-old Sumatran tiger, cleaning and feeding her tiny cub, just hours after its birth in the early hours of December 12.

       Sumatran tigers, from Indonesia, are the rarest and smallest subspecies of tiger, with the latest figures suggesting that only 300 remain in the wild.

       Newborn tigers' eyes remain closed for the first few days after birth, and the cub will remain tucked away in the cubbing den until its first vaccinations, when vets and zookeepers will also be able to determine its sex.

       However, the zoo's hidden "cubcam" has managed to capture some milestone moments, including the youngster taking its first wobbly steps.

       Lucy Reed, keeper, said: "The chunky little cub is doing really well in mum's excellent care, and definitely takes after dad Asim in terms of size and strength.

       "We knew Gaysha was nearing full-term as we'd seen her belly grow rapidly over the previous few weeks, so we made her a special cubbing den in anticipation.

       "At the moment, while we're still keeping a close eye via cubcam, we're also taking care not to disturb the family so that they can bond together."

       Born almost a year to the day since Gaysha first arrived at London Zoo from Denmark, the almost three-week-old cub is yet to be named.

       Originally expected to be part of a litter of three, the cub's two siblings did not survive labour.

       However, the birth is still a boost for a global breeding programme working with zoos from around the world to protect the species.