China will no longer rely on executed prisoners as a source of transplant organs within two years, a health minister said according to state media Thursday.

High demand for organs in China and a chronic shortage of donations mean that death row inmates have been a key source for years, generating heated controversy.

International human rights groups have long accused Chinese authorities of harvesting organs from executed prisoners without their consent or that of their families -- allegations the government has denied.

"Chinese organ transplants will completely end their reliance on donations from executed prisoners within two years," said Huang Jiefu, the vice health minister, according to the state-run China News Service.

Beijing has made similar pledges before, but Huang's comments represented the shortest timetable it has offered. It was not clear whether he was referring to ending the practice in its entirety.

The country was setting up a voluntary donation system, he said, with more than 1,000 organs collected since the first of 38 centres opened two years ago.

China banned trading in human organs in 2007, but demand for transplants far exceeds supply in the country of 1.3 billion people.

Organ donations are not widespread as many Chinese believe they will be reincarnated after death and therefore feel the need to keep a complete body.

An estimated 1.5 million patients need transplants every year but only around 10,000 are carried out, according to official statistics, opening the door to forced donations and the illegal sale of organs.

In 2009 state media quoted a health ministry spokesman saying the rights of death-row inmates were respected and written consent from prisoners was required before their organs could be harvested.

China executed around 4,000 prisoners last year, a 50 percent drop since 2007, according to US-based advocacy group the Duihua foundation.

Huang's remarks followed an earlier statement by a senior health ministry researcher that China will start phasing out the use of executed prisoners as a source of organs for transplants next year.