Sri Lankan authorities issued landslide warnings on Sunday as rains continued to lash areas already devastated by a powerful cyclone, with the death toll rising to 627. 

A series of tropical storms and monsoon rains have battered Southeast and South Asia, causing landslides, flooding vast regions, and isolating communities from Sumatra island's rainforests to Sri Lanka's highland plantations. 

Over the past two weeks, at least 1,826 people have died due to natural disasters sweeping across Sri Lanka, Indonesia, Malaysia, Thailand, and Vietnam.

In response, Indonesia's president vowed on Sunday to increase aid efforts, as demonstrators rallied following the country's death toll surpassing 900.

In Sri Lanka, more than two million people-nearly 10 percent of the population-have been affected by last week's floods and landslides triggered by Cyclone Ditwah, the worst to hit the island this century.