BEIJING, August 21 -- Construction of the 2010 Shanghai World Expo site officially started on Saturday, a symbolic moment as the city bids to turn the multi-billion dollar project into a spectacular reality.

    The first batch of construction includes 11 roads that will connect the venue with the rest of the city and provide a valuable addition to the city's overall infrastructure capacity upon completion next year.

    According to the plan, 30 roads will be built or expanded for the fair, 18 of which will be located in Pudong and the rest in Puxi.

    Vice-Mayor Yang Xiong attended the opening ceremony for expo venue construction and called the whole project a "complicated and systematic" task.

    He also revealed that 65 countries and international organizations had confirmed their participation so far, with three more registering last week.

    Construction of the 5.28-square-kilometre site near the Huangpu River in Pudong is scheduled to be completed by the end of 2009, with a budget of 30 billion yuan (US$3.62 billion). However, Xinhua News Agency previously reported the budget could be as high as 300-400 billion yuan (US$36-48 billion), as the original budget only covers construction of the site itself.

    According to Shanghai World Expo Land Holding Corporation, the main infrastructure construction operator, the entire project will involve nearly all kinds of urban construction, such as landscaping, underground work and flood prevention facilities.

    Four subways will pass through the site, all of which are under construction. They are expected to help carry half of the anticipated 70 million visitors.

    Construction of exhibition pavilions for the 200 participants is expected to start in the first half of next year.

    Organizers said they would come up with the design of the Theme Pavilion and the Chinese Pavilion at the end of this year.

    The city has undertaken its largest ever relocation project because of the expo. It is estimated that 54,000 individuals and 272 enterprises will have been relocated for the expo.

    According to organizers, about 30 per cent of the land has already been vacated and flattened.