Herbert Smith has won a role on what is set to be the world's largest-ever initial public offering (IPO) as the Agricultural Bank of China (AgBank) goes public.

The UK top 10 firm is advising the underwriting banks on the landmark listing, which was initially valued at as much as $30bn (£20.2bn), although market estimates have since been tempered by a drop in China's stock market, with a figure of $23bn (£15.5bn) now thought to be more likely.

The Herbert Smith team is being led by Beijing corporate partner Tom Chau (pictured), with the underwriters including Goldman Sachs, Morgan Stanley, JP Morgan, China International Capital Corporation, Deutsche Bank and Australia's Macquarie.

Meanwhile, US firm Davis Polk & Wardwell has taken the key role for AgBank, fielding a team headed up by corporate partner Show-Mao Chen.

AgBank, one of China's 'big four' banks, was founded in 1951, becoming the first commercial bank to be established in the People's Republic of China.

The listing is one of only a handful in Chinese history to be launched on both the Hong Kong and Shanghai stock exchanges.

Stephen Mok, a corporate partner in the Hong Kong office at Eversheds said: "This is a bold move for this state-owned bank, the fourth and last to go public, and highlights just how hungry China's economy is.

"As with other large-scale listings of major Chinese state-owned enterprises, the AgBank IPO is very much politically driven as much as anything else. It will be interesting to see the results of this IPO given the less than ideal timing of its launch and the relatively weak market sentiment."

The world's largest IPO to date is the 2006 listing of Industrial and Commercial Bank of China (ICBC), which raised a reported $22bn (£14.8bn).

ICBC was also the first Chinese company to be listed on multiple stock exchanges.