Two newborn pandas have become the latest additions to the Madrid Zoo when they were born on Tuesday.

The hairless, pink twins were born to a giant panda after being conceived through artificial insemination, and each weighs 5 ounces.

It will be a few days before vets can determine their gender.

They are the first pandas born in the Madrid Zoo since it unveiled one named Chu-Lin in 1982, the first panda born in captivity in Europe. That one became wildly popular and a symbol of the Spanish capital.

Spain's National Research Council, which took part in the recent insemination along with scientists from China, said pandas have been born in Europe four times, twice in Madrid and two other times in Vienna.

The council said there are only an estimated 1,600 pandas left living in the wild in China, their numbers depleted by destruction of their habitat.

The Madrid Zoo has four of the endangered animals: the newborns and their parents, mother Hua Zui Ba and father Bing Xing.

That couple was a goodwill gift from the Chinese government to King Juan Carlos and Queen Sofia during a visit to China in 2007.

The zoo used artificial insemination, because it is extremely difficult for pandas in captivity to conceive naturally.

The new babies' mother, whose name means Flowery Mouth, licked them clean upon birth and the cubs are taking turns being nursed.

As per panda custom, the father remains aloof and stays away from the babies.