Chinachem Charitable Foundation, which is also staking a claim to Wang's fortune, is opposing Chan's request to replace British handwriting expert Audrey Giles with Australian Paul Westwood. The hearing has been adjourned until Thursday.

Foundation counsel Dennis Chang had earlier told Judge Johnson Lam Man-hon he understood Giles "has given strong evidence that Nina Wang's signature is not genuine," and is instead a high-quality fake.

ADVERTISEMENT

Chang claimed Giles' opinion is even stronger than that of the foundation's own handwriting expert, Robert Radley, who is also British.

Chan, 49, who claims he was Wang's secret lover, possesses a 2006 will that purportedly leaves her assets to him.

The foundation holds a 2002 will, which is undisputed, that leaves Wang's assets to the charity and family members.

Chan's side had earlier announced its intention to apply for permission to use Westwood's evidence.

The foundation opposes the application and is demanding a clear explanation for the switch.

Meanwhile, the foundation has sent solicitor Keith Ho Man-kei to pick up the original documents from London to be sent to Australia in the event Chan's application is approved.

Outside court Chan's solicitor Jonathan Midgley, said: "What we're interested in is finding the truth and what Nina Wang's intentions were."

The dispute over the will began after Wang died on April 3, 2007, aged 69.

She became one of Asia's richest women during the final years of her life, thanks to the vast business empire her husband, Teddy Wang Tei-huei, started building in the 1960s.

Following Teddy Wang's kidnap in 1990 and presumed death in 1999, Wang and her father-in-law, Wang Din-shin, engaged in bitter legal battles over his estate.

Nina Wang was at one point charged with forgery but the Court of Final Appeal ruled in 2005 that she was the rightful beneficiary of her husband's estate.