A motorbike crossing a bamboo bridge across the Mekong River in Kompong Cham, Cambodia.

Five Southeast Asia countries are set to bridge China and India - Asia's two largest economies - but whether or not they boost economic development remains to be seen, according to analysts at ANZ bank.

Cambodia, Laos, Myanmar, Thailand and Vietnam - which ANZ calls the Greater Mekong 5 (GM-5) - have the potential to connect South, Southeast and East Asia, which could help the region become one of the world's fastest growing, it said.