Thailand's premier said Thursday that it was impossible to protect all of Bangkok from the country's worst floods in decades, describing the situation as a "national crisis".
"We cannot block the water forever," Prime Minister Yingluck Shinawatra told reporters, adding that the government would choose which parts of the city to allow the water through to minimise the impact.
"We need areas that water can be drained through so water can flow out to the sea," she said.
The government has reinforced the city's floodwalls in an attempt to prevent the floods pouring into the densely populated city from the central plains, which are several metres under water in places.
Efforts to keep the country's economic and political heartland dry have been complication by a seasonal high tide and have also taken a heavy toll on areas outside of the capital.
"Flood waters are coming from every direction and we cannot control them because it's a huge amount of water. We will try to warn people," Yingluck said.
"This problem is very overwhelming. It's a national crisis so I hope to get cooperation from everybody."
Three months of heavy monsoon rains have killed 320 people, damaged the homes and livelihoods of millions of people, mostly in northern and central Thailand, and forced tens of thousands to seek refuge in shelters.