Shanghai Tunnel Engineering Company has secured an SGD622 million (US$ 456 million) contract to build a 2.5-km-long underground link between Changi Airport Terminal 5 (T5) and Terminal 2 (T2) in Singapore. 

The project involves constructing a 9 m-wide tunnel for baggage transfers for travelers with connecting flights, along with tunnels exceeding 6 m in width in each direction for an underground train system connecting T5 and T2. These tunnels will accommodate an automated people-mover system and a separate system for baggage handling. A new 2.6 km underground automated people-mover system will operate at speeds of up to 80 km/h, transporting 10,800 passengers/hour. As part of the ongoing infrastructure development at the new 1,080 ha Changi East development, the T2 Connection will link T5 with Changi's existing terminals upon the opening of the mega terminal in the mid-2030s. The contract also includes restoring airport infrastructure and road surfaces affected by the works, with an expected completion date of October 2028. 

Plans entail establishing a direct connection between T5 and Tanah Merah Ferry Terminal, as well as extending the Thomson-East Coast MRT Line to pass through T5, connecting the upcoming Sungei Bedok station with Changi Airport. Construction of the new terminal is slated to commence in 2025.