New Delhi, Jan. 23 -- Southeast Asia's demand for coal is growing faster than anywhere else in the world, undermining efforts to lower carbon emissions that contribute to global warming.

Regional coal demand will rise by more than 4% a year through the end of the decade, driven by rising needs for electricity as economies grow across the region of more than 600 million, according to a recent International Energy Agency report. Indonesia, a nation of about 285 million people, will account for more than half of that, followed by Vietnam.

The trends raise questions over the $15.5 billion-dollar deals both countries signed in 2022 in Just Energy Transition Partnerships, or JETP, to help fund their renewable energy transitions. Moves under U...