Mei Xiang gently places her cub on the floor of her den. The panda cub has a round belly, which indicates that it is nursing well. (Smithsonian National Zoo)

At just six days old, the National Zoo’s new panda cub isn’t quite ready to stand on its own away from mom.

According to zoo officials, the cub’s mother, giant panda Mei Xiang, tried putting her baby down at 3:37 a.m. on Thursday morning. For about 30 seconds, the small cub -– palm-sized at 4.8 ounces when it was examined over the weekend –- rocked back and forth on four tiny paws squawking loudly until Mei Xiang picked it up again.

“It’s a completely normal behavior for her to set her cub down and take a few steps away,” Jen Zoon, a National Zoo spokesperson, said of the panda mom. “She’s basically seeing how it does when she’s not touching it or holding it,” said.

As the cub grows, Zoon said, it will stand on its own for longer and longer periods before it squawks again for Mei Xiang to pick it up.

For now, Mei Xiang spends almost all her time cradling her infant close, Zoon said, and she wakes up about every 30 minutes to nurse the baby. In video footage of the cub’s brief moments trying to stand on its own, zookeepers noted the baby’s rounded belly, a sign that it is nursing well.

Zoon said that Mei Xiang was offered food but refused, which is normal for a panda that has recently given birth. She drank 56 ounces of diluted apple juice on Thursday. Mei Xiang started eating again two weeks after the birth of her son Tai Shan in 2005.

The newest cub’s gender has not be determined yet.

How giant panda cubs grow

The Zoo operates a round-the-clock panda cam for spectators to watch Mei Xiang, and now her newborn, any time.