Shanghai Mayor Han Zheng announced on Sunday that the city will hold five trial operations in preparation for the upcoming World Expo. He also addressed public concerns regarding the Expo's budget.

Han said the trial operations will be held from April 20- 25 and will test Expo security, transportation, visitor services and logistics. At least two of the tests will require the joint efforts of about 300,000 to 500,000 people.

Han expects the tests to affect the city's transportation, but said they were necessary in order to find potential logistical problems. "We hope that all visitors will be able to enjoy their stay in Shanghai, while Shanghai citizens can keep their normal lives during the Expo," Han said.

According to Hong Hao, director of the Bureau of Shanghai World Expo Coordination, Expo staff and construction workers will be mock visitors during the trial operations.

Han also dismissed rumors that have been circulating on the Internet, claiming that the Shanghai Expo has an investment of 400 billion yuan and is the most expensive in Expo history. "The total investment of the Shanghai Expo, including construction and operation costs, is 28.6 billion yuan (US$4.19 billion). All investments will be released to the public."

The construction budget approved by the State Council is 18 billion yuan (US$2.64 billion), including construction of the Expo village, permanent pavilions and Expo infrastructure.

Expo operation costs are estimated to reach 10.6 billion yuan (US$1.55 billion). "They will be financed through marketing channels such as tickets sales, sponsors, licensed Expo products, and etcetera. We expect to raise more than 10 billion yuan through these methods," said Han.