China's Premier Wen Jiabao has said corruption is the biggest threat facing the ruling Communist Party, warning of a change in the "nature of power" if it is not curbed.

His comments come amid growing public anger in China over official corruption, which senior leaders have said poses a threat to their grip on power ahead of a major leadership transition later this year.

"Corruption is the most important threat facing the ruling party," Wen said in comments published late Monday on the website of the State Council, China's cabinet.

"If the matter is not handled properly, the nature of power may change. This is a very grave challenge we are facing."

The Chinese public is increasingly intolerant of perceived official corruption, with a growing number of people taking to the streets and social networking sites to criticise the government.

In December, villagers in the southern province of Guangdong lived under police blockade for more than a week after driving out Communist Party leaders they said had been stealing their land for years.

Earlier this year, President Hu Jintao ordered Communist Party leaders to fight harder against corruption and be more disciplined ahead of a major leadership transition that begins this year.

The 10-yearly transition of power in China begins in October or November this year when Hu ends his second five-year term as party head. He will end his presidency in 2013 when the rest of the government resigns.