Rescue workers reinforced make-shift walls and sand-bags around Bangkok as the worst floods in half-a-century threatened Thailand's low-lying capital after swamping entire provinces in the north.
Prime Minister Yingluck Shinawatra sought to reassure Bangkok's 12 million people they would largely escape floods that have swept over a third of Thailand since July, killing at least 297 people.
The north, northeast and centre of Thailand have been worst hit and Bangkok - much of it only two metres above sea level - is at risk as water overflows from reservoirs in the north, swelling the Chao Phraya river that winds through the densely populated city.
Ms Yingluck said Bangkok is well fortified after authorities raised embankments at the three outer areas.
Despite official assurances, residents stocked up on bottled water, instant noodles, rice and canned goods, emptying shelves in some major markets. Many parked their cars in elevated garages, or piled sand-bags in front of shop-houses and homes.
Water released from several dams should reduce the chance of floods, Ms Yingluck said, as northern run-off water approaches Bangkok over the weekend, coinciding with high estuary tides that hamper the flow of water into the sea.
The US dispatched a C-130 military transport aircraft with 1,000 sand-bags and 10 Marines in a humanitarian mission, US embassy spokesman Walter Braunohler said in a statement.
Twenty-five of Thailand's 77 provinces are flooded with 4m acres of farmland under water - about 16 times the size of Hong Kong. Nearly 800,000 homes have been destroyed or damaged. Thousands of people huddled in evacuation centres.
Ayutthaya, Pathum Thani and Nakhon Sawan provinces north of Bangkok have been devastated. Floods have swallowed up homes, swamped streets and destroyed industrial parks, partly a result of desperate measures to shield the capital.
