The Constitutional and Mainland Affairs Bureau, which is in charge of the expo work, says it is not yet ready to give details, even though the event organisers expect a draft design for the Hong Kong pavilion to be sent to Shanghai soon.

Executive councillor Selina Chow Liang Shuk-yee, former chairwoman of the Tourism Board, said she knew nothing about the preparations or which bureau was responsible for it.

'We haven't heard anything about how the government is going to prepare for it.

'But we're confident it will come up with a design that showcases Hong Kong's uniqueness and will tell us when things are ready,' she said.

Hong Kong and Macau are being given special treatment at the event, with separate pavilions within the China zone that will be bigger than those allotted to mainland cities and provinces.

Each will have 800 square metres in a separate pavilion compared to 600 square metres occupied by mainland entities in the main 20,000 square metre China pavilion.

A spokesman for the organising committee said Hong Kong was about to finish the draft design and would send it to Shanghai soon.

The Constitutional and Mainland Affairs Bureau said the exhibition was one of the 'major international events to be hosted by China after the 2008 Olympics' and the Hong Kong government was honoured to be invited.

'It provides a good opportunity to showcase Hong Kong's cosmopolitan character and unique advantages under the 'one country, two systems' principle. Further details regarding Hong Kong's participation are being worked out,' the bureau said.

Lily Chiang Lai-lei, chairwoman of the General Chamber of Commerce, said little was known in Hong Kong about the event, which offered important business opportunities in all sectors.

'We strongly urge much better planning as we do not see any effort towards that,' she said. Dr Chiang also said the expo should not be seen in isolation.

'If we take the Beijing Olympics next year, the Asian Games in 2009 and World Expo 2010 together, we will find they provide an excellent opportunity for us to promote the Hong Kong brand.

'There should be some master plan to promote Hong Kong in all of these.'

A Trade Development Council spokesman said the body was not involved in the preparation work.

The chairwoman of Wan Chai District Council, cultural critic Ada Wong Ying-kay, said the city must engage with the public over the event as it represented the city to the world.

'The government must involve the public on the preparation,' she said.

'I hope it will start a community-wide discussion now.

'The presentation shouldn't be about how the Hang Seng Index keeps rising and models of our major works projects.

'It should be about how city planning and technology can create a better city and better life.'

The theme of the Shanghai expo - Better City, Better Life - focuses on urban life.