The Bangkok governor has made a desperate plea for sandbags as the city is on the brink of flooding from bursting dams.

Bangkok Governor Sukhumbhand Paribatra told media that “every minute is critical” as he appealed for 1.2 million sandbags to prevent a deluge from a “huge amount” of water from northern dams.

“We urge the government to give those bags now. Otherwise, it will be too late,” Paribatra urged.

Thailand is engulfed by the worst flooding in 50 years, after heavy monsoon rains forced authorities to release water from the dams in the north of the country.

So far at least 315 people have been killed and 8.8 million more affected as monsoon rains and floods have swept across 61 of Thailand’s 77 provinces over the past three months, the Disaster Prevention and Mitigation Department confirmed. Some 930 industrial plants, employing more  than 300,000 workers, have been swamped and floodwaters are still present in 27 provinces.

Thailand prime minister Yingluck Shinawatra is seeking avoid the capital city being submerged, but sandbag shortages are widespread, with the price jumping 15-fold to 75 baht (£1.54) each.

Already, four eastern districts in Bangkok, a city densely populated with 9.7 million people, are flooded with about half a metre (1.6 feet) of water.

Sean Boonpracong, a spokesman for Thailand’s Flood Relief Operation Command, said a “lack of accurate information from the field” makes threat of flooding in Bangkok unclear.

However, Sukhumbhand admitted there was a high risk of flooding in suburban parts of northern Bangkok, including areas near Don Mueang airport, which handles mostly domestic flights and where the government has set up a flood relief centre. He said he would expedite the building of levies along canals in nearby Rangsit.

“At the moment we are surrounded by water,” said Jate Sopitpongstorn, a spokesman for the Bangkok Metropolitan Administration. “What we are afraid of over the next two or three days is whether the sandbags we put in place will be able to hold.”

City officials are monitoring flood defenses along the Chao Phraya river, whose banks are lined with hotels including the Peninsula and the Shangri-La, as well as the Bank of Thailand. Bangkok sits near the bottom of the river basin, a low-lying area in which water drains from Chiang Mai in the north down to the Gulf of Thailand.

China and Malaysia are expected to be the most affected by supply chain disruptions, particularly for office machinery, including hard-disk drives, for which Thailand accounts for 60 percent of global production.

Thailand’s Cabinet today agreed to widen the 2012 budget deficit by 50 billion baht to fund flood reconstruction, the damage of which, has been estimated at 120 billion baht.