China's former leader Jiang Zemin - who steered the country through a transformational era from the late 1980s and into the new millennium - has died this morning at the age of 96, state news agency Xinhua said.

Mr Jiang took power in the aftermath of the Tiananmen Square crackdown and led the world's most populous nation towards its emergence as a powerhouse on the global stage.

The major bodies of China's ruling Communist Party bodies announced his death through a letter that expressed "profound grief".

"Jiang Zemin passed away due to leukemia and multiple organ failure in Shanghai at 12.13 pm on 30 November, 2022, at the age of 96," Xinhua reported.

His death came after all medical treatments had failed, it said.

"Comrade Jiang Zemin was an outstanding leader... a great Marxist, a great proletarian revolutionary, statesman, military strategist and diplomat, a long-tested communist fighter, and an outstanding leader of the great cause of socialism with Chinese characteristics," Xinhua quoted the letter as saying.

Concerns over Mr Jiang's health had been raised when he did not attend the opening or closing ceremonies of last month's Communist Party Congress.

When Mr Jiang replaced Deng Xiaoping as leader in 1989, China was still in the early stages of economic modernisation.

By the time he retired as president in 2003, China was a member of the World Trade Organization, Beijing had secured the 2008 Olympics, and the country was well on its way to superpower status.

Analysts say that Mr Jiang and his "Shanghai Gang" faction continued to exert influence over communist politics long after he left the top job.

He is survived by his wife Wang Yeping and two sons.

Flags at major Chinese Communist Party and government buildings in China and worldwide are set to be flown half-mast.

The order, from Mr Jiang's funeral arrangement committee, applies from today until the date of his funeral, yet to be announced, according to state broadcaster CCTV.

"During the serious political turmoil in China in the spring and summer of 1989, Comrade Jiang Zemin supported and implemented the correct decision of the Party Central Committee to oppose unrest, defend the socialist state power and safeguard the fundamental interests of the people," CCTV added.

Chinese state media all posted the same black-and-white photo of a chrysanthemum on their official accounts on social media platform Weibo.

Mr Jiang's entry on Baidu Encyclopedia, a Chinese site similar to Wikipedia, also turned black-and-white.

However, his legacy remains mixed and his critics numerous.

Mr Jiang was criticised for failing to solve new problems created by China's economic rebirth: rampant corruption and inequality, environmental degradation and state sector reforms which caused mass layoffs.

"There were a lot of corruption problems at the time, but he was a lively and jovial person... Maybe that's the image people will keep of him," Beijing resident Wang Yi told AFP.

"The media was also freer in his time to report critically on society's problems."