THAILAND - The Natural Resources and Environment Ministry's Botanical Garden Organisation will invest Bt50 million (S$2.1m) to build Thailand's first canopied walkway in the Queen Sirikit Botanical Garden in Chiang Mai's Mae Rim district, a senior official said Monday.

The 350-by-20-metre walkway - to help research and stimulate ecotourism - is still at the design process and should be completed by 2010, organisation president Withoon Karuna said.

He added that before the project starts, an environmental impact assessment would be done to prevent damage to the 6,500rai garden, and if completed as planned, the walkway would be Southeast Asia's longest canopied walkway.