Berlin zoo has said its resident panda Meng Meng has delivered twins, the first time one of the endangered animals has given birth in the country.

“Meng Meng became a mom – twice! We are so happy, we are speechless,” the zoo tweeted on Monday, posting a video of Meng Meng guiding one of her pink cubs to feed.

Pandas are notoriously difficult to breed, making such births rare.

The panda delivered its first cub on Saturday evening. About an hour later, a second baby was born.

“Meng Meng and her two cubs coped well with the birth and are all in good health,” the zoo’s director, Andreas Knieriem, said.

Meng Meng looks after one of her newborn twins at Berlin zoo on Saturday. Photograph: Zoo Berlin handout/EPA

At birth the pink cubs, with their fine white down and disproportionately long tails, bear little resemblance to the adult black and white bears.

Their sexes have not yet been determined, the zoo said. They weighed 136g and 186g.

On loan from China, Meng Meng and the male panda Jiao Qing arrived in Berlin in June 2017 to great fanfare.

In what is known as “panda diplomacy”, China has dispatched its national treasure to about a dozen countries as a symbol of close relations.

The zoo pays $15m in a 15-year contract to host them, with most of the money going towards a conservation and breeding research programme in China.

The cubs born in Berlin must be returned to China within four years after they have been weaned.

China has previously given three pandas to Germany but the last one, Bao Bao, died in Berlin in 2012 at the age of 34, having become one of the oldest male pandas in the world.

About 1,864 pandas remain in the wild in China, up from around 1,000 in the late 1970s, according to the environmental group WWF.

Just over 400 pandas live in zoos around the world, in conservation projects set up with Beijing.