Construction on the site of the Beijing World Horticultural Expo and accessory infrastructure are almost finished, and the site will be put into trial operation on April 5, Zhou Jianping, executive deputy director-general of the Beijing World Horticultural Expo Coordination Bureau, said.

The bureau's staff are now working around the clock in preparation for major events to be held during the expo, including the opening ceremony, said Zhou, who also is a member of the Chinese People's Political Consultative Conference National Committee, China's top advisory body, on the sidelines of the body's annual session that ended Wednesday in Beijing.

The expo, to be held in Beijing's Yanqing district from April 29 to Oct 7, is expected to receive 16 million visits from people around the world, he said. As of now, 110 countries and international organizations have confirmed they will attend the expo, Zhou said.

"Plants will be the major role of the expo, and through the expo we hope to spread ecological concepts and present a harmonious relationship of interdependence between man and plants," he said.

The expo also will promote exchanges and understanding between different countries and improve China's horticulture, he said. A special garden with the Belt and Road Initiative as the theme will be presented during the expo, he said.

More than 100 gardens featuring characteristics of various countries and different regions in China, with 1,200 kinds of plants, will be presented during the expo, he said. In addition, more than 2,500 various cultural events will be held, he added.

Some of the expo's facilities will be reused for the Winter Olympics, which will be held in Beijing and neighboring Hebei province in 2022, he said.