MANILA Climate change could 'seriously hinder' Southeast Asias development and efforts to reduce poverty, a new study released by the Asian Development Bank said Monday.

With its long coastlines and heavy dependence on agriculture and forestry, Southeast Asia is highly vulnerable to the effects of climate change, the Asian Development Bank (ADB) report said, warning 'The worst is yet to come.' 'Combating climate change requires urgent action on both adaptation and mitigation there is no time to delay,' the study said.

If the world continues with its 'business-as-usual' approach, the average cost of climate change for Indonesia, the Philippines, Thailand and Vietnam could be 'equivalent to losing 6.7 percent of combined gross domestic product each year by 2100 more than twice the global average.' Already, climate change has led to extreme weather events such as heat waves, droughts, floods and tropical cyclones in recent decades in the region, the ADB said.

It noted also that the annual mean temperature in the regions four biggest countries was projected to rise by 4.8 degrees Celsius by 2100 from the 1990 level.

It said that during this period, the sea level in the region was expected to rise 70 centimetres, while increasingly drier weather is likely in the next two to three decades.

'Southeast Asia is likely to suffer more from climate change than the global average,' it said.