There are few more symbolic displays of China's growing global clout than the sight of more than 40 African heads of state sitting in Beijing's Great Hall of the People.

These past two days the Chinese capital has played host to the largest ever gathering of African leaders outside their continent.

And they didn't leave disappointed.

Xi Jinping — China's 'President for life' — promised $82 billion for projects in Africa over the next three years.

It was the same amount he pledged when they all last gathered in 2015 — and he promised China wouldn't build 'vanity projects' or overburden African states with debt.

This year's Forum on China-Africa Cooperation was heavy with Beijing's usual rhetoric — 'win-win cooperation', building a 'community of common destiny' and notably many of the visiting leaders repeated such lines on state TV.

In his interview, Zimbabwe's new President, Emmerson Mnangagwa, summed it up.

Zimbabwe's president Emmerson Mnangagwa is one of the African leaders attending a meeting in Beijing. ( UN Geneva/flickr.com/CC BY-NC-ND 2.0 )

"There is now a transition to a new world order and those who don't see it are blind", he said.

The visiting leaders say China is building much-needed infrastructure that will help their countries develop, and they appreciate how it comes with fewer strings attached than Western funds.

But while the dignitaries were all smiles, some of the closest observers of the China-Africa relationship warned increasing caution was needed.

Musa Frimpong, a Ghanaian post-graduate university student in Beijing who also runs a start-up connecting Chinese businessmen to African counterparts, warned the nations needed to be wary when negotiating.

"We need to have a very good negotiation so that we don't give away all our resources in the name of infrastructure or investment," he said.

"We need to have that win-win cooperation where Africa gets a fair deal from the negotiating table."

Others worry China is pushing unsustainable levels of debt that could see smaller states forced to hand assets to Chinese control if they can't repay.

China, for example, holds more than three-quarters of the debt of strategically located Djibouti, which now hosts China's first overseas military base.

Chinese President Xi Jinping has promised $82 billion for projects in Africa in the next three years. ( Reuters: Mikal McAllister )

More than 70 per cent of Kenya's debt is owed to China, while Zimbabwe recently had to plea for debt relief in order to continue borrowing from Beijing.

Tinashe Mugari, a PhD student specialising in China-Zimbabwe relations at Sun Yet-san University in Beijing, said it could even be seen as a new type of colonisation.

"We can call it soft colonisation or neo-colonisation," he said.

"Because we're not seeing it now but eventually we will see that China is trying to be dominant on the African continent."

Mr Mugari is among those who believe China's infrastructure projects rely too heavily on Chinese materials and workers, and said cheap Chinese exports had flooded African markets and stunted the growth of domestic industries.

"The local industry in Zimbabwe is not going to develop", he said.

These are concerns Chinese leaders have now loudly heard.

Among the billions pledged by Mr Xi were investment in African enterprises and the cancellation of debts for some of the poorest nations.

Chinese officials appear to realise as the country's clout grows, so does the scrutiny.