China appointed a respected economist to its anti-graft body as it sought to stress its resolve in fighting the rampant corruption identified as one of the biggest challenges for the Communist Party.

Wang Qishan, China's top finance official, will join the party's Central Commission for Discipline Inspection, the state-run Xinhua news agency said Wednesday, as the party's five-yearly congress came to a close in Beijing.

Wang is best known for representing China in key economic talks with the United States and European Union.

The congress also approved an amendment to the party constitution to include a call for "attaching greater importance to conducting oversight of cadres", Xinhua said.

During the congress, delegates selected a 205-strong new party Central Committee and made other appointments to key party bodies such as the disciplinary commission, which is tasked with keeping officials in line.

Wang also has been tipped as a possible candidate for membership on China's top decision-making body, the Politburo Standing Committee, which now has nine members and is set to be unveiled in Beijing on Thursday.

"Its an interesting decision, as Wang is best known for relations with America and being a well-thought-of economic specialist," Kerry Brown, Professor of Chinese Politics at the University of Sydney, told AFP.

"He's very capable, so his capacity being put to work in this area shows a slight readjustment to emphasise the corruption issue," he said.

The party has been stained by a series of high-profile corruption scandals in recent years, including the spectacular downfall of one-time political star Bo Xilai who faces trial on charges of corruption and abuse of power.

The party's revised constitution includes a call to "strengthen oversight of principal leading cadres," referring to high-ranked members of the party.

President Hu Jintao said at a keynote address to the congress last week that a failure to tackle corruption by party officials could cause "the collapse of the party and the fall of the state".

China's ruling party has made a number of high-profile anti-corruption drives in recent decades, but they have done little to offset increasing perceptions of graft.

"There are many cases involving high-level officials, and cases involving huge amounts of money," a senior researcher associated with the Central Commission for Discipline Inspection told Xinhua earlier this year.

Reports of the huge wealth amassed by the families of top officials have intensified pressure on the party to counteract allegations of cronyism and corruption.

The New York Times said last month that the family of Chinese Premier Wen Jiabao owned assets worth $2.7 billion, a report which China called a smear.

The Bloomberg news agency previously estimated the family of Xi Jinping -- who is almost certain to be appointed head of the party on Thursday, and named president next year -- had assets worth $376 million.

Authorities have sought to suppress the reports in China.

Analysts doubt whether the party's discipline body, which is not an independent body, can be effective in reducing corruption.

"I think they will go through the motions of cracking down on corruption harder than before," Willy Lam, a Chinese political analyst at the Chinese University of Hong Kong told AFP.

"As long as the party is the only power centre, corruption will never be eradicated," he said. "anti corruption manoeuvres are just the party inspecting itself."

China ranked 75th of 182 countries on a corruption perceptions index published by advocacy group Transparency International in 2011.