BANGKOK: Thailand's government is preparing what it calls a ''master'' plan to manage water flows to prevent a repeat of the most damaging floods in decades, as foul water creeps along Bangkok's major roads towards the capital's commercial centre.

''The plan would mobilise all real experts to work in the same direction,'' said the Prime Minister, Yingluck Shinawatra, who has come under heavy criticism for mishandling the disaster, which has killed more than 427 people, affected the lives of 3 million others and crippled industry and crop production. ''To date we have taken many directions that never worked.''

Ms Yingluck's government has proposed that part of a $US26 billion recovery fund be used to better manage water systems and flood defences.

Analysts said when the floods receded the government would have to act quickly to reassure foreign companies, which have operated there since the 1980s.

Seven of Thailand's main industrial estates are flooded, knocking as much as two percentage points off the country's economic growth this year, analysts said.

An estimated one-quarter of the world's hard-drive output is under water in factories north of Bangkok, where the most severe flooding occurred.

Honda Motor Co has had to cut production by almost a third.

The United Nations is monitoring the potential for food shortages in parts of south-east Asia after flooding devastated rice and other crops in Thailand, Vietnam, Laos, Cambodia and the Philippines.

After saying inner Bangkok would probably escape flooding, Ms Yingluck conceded ''we cannot prevent flooding in all locations''.

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