A chimpanzee in a northwest China zoo has succeeded in quitting smoking, a habit that has troubled her for past 16 years.

Ai Ai, a 27-year-old mother chimp at Qinling Safari Park in Shaanxi Province, spent four weeks abstaining from smoking, by cutting her daily cigarette consumption step-by-step until ridding the habit entirely, a zookeeper said.

The zoo management decided to help the chimp quit smoking because it had been deteriorating her health, Xinhua news agency quoted the zookeeper as saying.

"She's served fried dishes and dumplings at every meal, alongside her usual diet of milk, banana and rice," he said without giving his name.

"I also put earphones on her so that she could enjoy some pop music from my Walkman."

The zookeepers tried every way to divert the chimp's attention from cigarettes: a walk after breakfast, a music session after lunch and gym after dinner.

"In the first few days, she squealed for cigarettes every now and then, but as her life became more colourful, she gradually forgot about them altogether," the zoo worker said.

Ai Ai became a smoker in 1989, shortly after her partner died. With the death of her second partner in 1997 and a daughter's moving away to the Shenyang Zoo in the northeast, the chimp became a chain smoker 'in solitude and grief'.