Seven people have died in Irrawaddy Division in the past two days, where high floodwaters and dangerous conditions have prompted warnings from local officials.

Villagers across Irrawaddy Division are abandoning their homes in droves after warnings that floodwaters would remain well over danger levels in the days ahead.

"Natural disasters can't be stopped once they start," Thein Sein warns delta residents in a speech broadcast on state TV.

Water levels are rising in the Irrawaddy and Pathein rivers, leaving residents concerned that dikes will not be able to withstand the growing pressure as monsoonal floodwaters move south into the Irrawaddy delta from affected regions further north.

The town of Padaung, ten kilometres south of Pyay, has been almost completely inundated. Locals from some 30 villages have been evacuated to safety.

A naval patrol boat came across a “suspicious looking” shipping trawler in the Gulf of Martaban at 6.30am.