TOKYO (AP) - Gohan and Aochan make strange bedfellows: one's a nine centimetre dwarf hamster, the other is a 1.2-metre rat snake.

Zookeepers at Tokyo's Mutsugoro Okoku zoo presented the hamster - whose name means meal in Japanese - to Aochan as a tasty morsel in October, after the snake refused to eat frozen mice. But instead of indulging, Aochan decided to make friends with the furry rodent, according to keeper Kazuya Yamamoto. The pair have shared a cage since.

"I've never seen anything like it. Gohan sometimes even climbs onto Aochan to take a nap on his back," Yamamoto said.

Aochan, a 2-year-old male Japanese rat snake, eventually developed an appetite for frozen rodents but has so far shown no signs of gobbling up Gohan - despite her name.

"We named her Gohan as a joke," Yamamoto chuckled. "But I don't think there's any danger. Aochan seems to enjoy Gohan's company very much."

The Tokyo zoo also keeps a range of mostly livestock animals, and promotes "cross-breed interaction," according to Yamamoto.

But Gohan and Aochan's case was "was a complete accident," Yamamoto said.