China will abolish the transplanting of organs from executed prisoners within five years and try to spur more citizens to donate, a top health official says.

Rights groups call transplants from condemned prisoners a form of abuse and allege that the government, which executes far more people than any other country, pressures them to donate organs. The government, however, says prisoners volunteer, and that the change is being made because prisoners are less healthy than the general population.

The official Xinhua news agency quoted the vice-health minister, Huang Jiefu, as saying on Thursday that prisoner organ donations are not ideal because condemned inmates have high rates of fungal and bacterial infections.

"Therefore, the long-term survival rates for people with transplanted organs in China are always below those of people in other countries," Xinhua paraphrased Huang as saying.

Organ donations from condemned prisoners will be abolished within five years,Huang told a conference in Hangzhou in eastern China.

Xinhua said hospitals will instead rely on a national organ donation system that is being set up. It said trial systems have been launched in 16 provinces.

China refuses to say how many prisoners it puts to death each year. Amnesty International estimates it is in the thousands, far more than the number of executions in all other countries combined. The San Francisco-based Dui Hua Foundation estimates China executed 5,000 people in 2009.