PUBLIC funds could be boosted by around $4 billion if plans to sell under-utilised government sites are backed by Beijing. Last year the disposal of four unwanted government plots reaped $1.4 billion. Nine sites have been targeted for sale this year. But the redevelopment programme will remain on hold until it is discussed by the Sino-British Land Commission. As yet no date has been fixed for a meeting. Seven of the nine areas have to be included with new sites in the 1993-94 land disposal programme, which must be authorised by the Chinese side. Two were approved last year, but only sold in January. Despite the Government's effort to step up the programme of redeveloping under-utilised sites, the controversial Oil Street site in North Point, which is the headquarters and storage depot of the Government Supplies Department, is still not included in this year's sale list. The Director of Audit and the Legislative Council Public Accounts Committee criticised inadequate planning and management for the delay in deciding how to relocate the depot. The relocation plan could have been worth $1.6 billion but was shelved after 12 years of study. A report on the development of the Oil Street site is some months away. The Director of Planning, Dr Peter Pun Kwok-shing, said an inter-departmental committee - the Committee on the Redevelopment of Under-developed Government Sites - would decide which sites could go for public auction. Dr Pun said the committee, set up in 1990, had shortened the time taken to identify under-developed sites and relocate the occupiers. He expected more sites would be put on the market in the next few years. ''We have a very long list. We have to first ensure a particular site can be better used if it is given new development parameters,'' he said. ''And we have also to make sure the user can be removed.'' Sites in Kwai Chung and Cox's Road were sold in January for a total of $460 million. The residential site at Cox's Road, with a gross floor area of 8,800 square metres, fetched $360 million and the industrial site in Kwai Chung, with a gross floor area of 8,700 square metres, went for $100 million. The Planning Department has already set out the development parameters of three of the seven other sites, which can immediately go for sale if the Land Commission approves. The first is the 30,000-square-metre commercial site at King's Road, used as a store by the Information Services Department. The second is a 47,000-square-metre residential site at Tung Yan Street in Kwun Tong, where the district office was housed. Another residential site in Farm Road, with a gross floor area of 55,000 square metres, was previously the office of the Highways Department but has been vacated. Sites in Apleichau Bridge Road, Castle Peak Road, High Street and King's Road have also been identified for sale this year. But their development parameters have still to be determined. The Land Commission last year agreed to the disposal of up to 159 hectares of land, about 28 hectares of which was earmarked for commercial, residential and industrial development. Under-used government properties in Aberdeen Main Road, King's Park Rise, Severn Road and Rose Street were sold to developers as part of that programme for $1.4 billion.