The brother of late tycoon Nina Wang Kung Yu-sum is pushing to replace the “big four” accounting firm managing his sister’s HK$137 billion (US$17.6 billion) estate, saying the company is charging too much and failing to fulfil its responsibilities. Wang’s younger brother Dr Kung Yan-sum, who sits on Chinachem Group’s executive committee and is chairman of the Chinachem Charitable Foundation, said he had filed a letter with the Department of Justice on Wednesday, seeking to remove PwC as interim administrator of the estate. Kung’s move marked the latest row in a long-running saga over the assets of Wang, who died of cancer in 2007 aged 69. The department’s involvement stems from a court ruling four years ago for the secretary for justice, who acts as protector of charities, to help fulfil Wang’s last wishes. “Their charges are expensive and they haven’t achieved what they should, so I want to replace them,” Kung said. PwC charges more than HK$60 million a year – four times the annual limit Chinachem Group could allocate for charity work, he added. Kung criticised PwC for not being transparent enough over the departure of group CEO Sunny Yeung in 2016. He claimed he was also asked by PwC to take a year off when Yeung left the company. Kung said his late sister wanted to carry out more charitable works with the help of the foundation. He could not say if or when PwC would be replaced because the department’s agreement was needed on the firm’s removal. In 2015, the Court of Final Appeal ruled the foundation and justice secretary had to come up with a scheme to fulfil Wang’s last wishes as spelt out in her 2002 will. The scheme would have two objectives: the establishment of a supervisory body and arrangements for the creation of a Chinese Prize, which would be the equivalent of the Nobel Prize. Wang wished to have the supervising organisation jointly formed by the secretary general of the United Nations, the premier of China and Hong Kong’s chief executive. In a reply to the Legislative Council in December, the government revealed the core assets of the estate were worth about HK$137 billion as of last August 31 and comprised the assets of Chinachem Group companies. In a press conference, Chinachem legal head Mary Wong did not comment on Kung’s move, but said management of the foundation was separate from the group. The joint administrators of the Estate of Nina Wang said they strongly refuted the allegations made by Kung against them and PwC in the press conference, calling them “misconceived and to a large extent factually incorrect”. “The administrators’ fee represents actual time spent by a sizeable professional team on an assignment which is large in scale and complex and in any event all fees incurred were approved by the Chinachem Charitable Foundation and the Department of Justice before payment,” its statement said. A PwC spokesman said the company would not comment on its clients or their business matters for confidentiality reasons. The department said it had received Kung’s letter and was considering the matter. It added it would to implement the charity scheme as soon as possible and had taken out an application on March 29 to seek the court’s directions. A directions hearing was expected to take place on June 13. In 2010, the foundation won a lengthy legal battle with feng shui master Peter Chan Chun-chuen, who was revealed to be Wang’s lover, and was awarded the estate. The following year, Chan lost his final appeal in Hong Kong’s top court over his claim to the estate.