BANGKOK >> Thailand’s prime minister is warning that rising floodwaters which have wreaked havoc across the nation are now threatening the capital, Bangkok, as the death toll from the worst monsoon rains in decades rose Saturday to 253.

Prime Minister Yingluck Shinawatra said the flooding — which has severed rail links with the north, shut dozens of highways and swamped ancient Buddhist temples in the city of Ayutthaya — has reached a crisis level.

Bangkok has so far been spared serious damage, but many fear it could be inundated as large amounts of water flows from submerged northern rice fields toward the Gulf of Thailand. That critical runoff is expected to be impeded by high ocean tides in mid-October, and Tropical Storm Nalgae is also forecast to bring new rain in the days ahead.

In a radio message Saturday, Yingluck said authorities are hoping to ease the crisis by installing up to 400 water pumps along the Chao Phraya River, which snakes through Bangkok, to help push water to the sea. Seven canals will also be dug on the outskirts of the city, she said.

Yingluck said government agencies are struggling to cope because "the water volume is extraordinary and is beyond expectations."

"It is now going to have a direct impact on Bangkok," Yingluck said in a televised speech Friday.

Bangkok Gov. Sukhumbhand Paripatra said the situation in the capital — where authorities have piled thousands of sandbags along the banks of rising rivers — is currently under control.

But he said he has ordered city officials to prepare for evacuations if necessary. The city government has also been stocking emergency supplies of food and water.

Yingluck visited a pumping station on the outskirts of Bangkok on Saturday, and said she believes a series of drainage tunnels under the city will be able to handle the floods.

The Department of Disaster Prevention and Mitigation said 253 people have been killed in the disaster, mostly from drowning, since a series of tropical storms began hitting Thailand at the end of July. It said 8 million people in 60 of the country’s 77 provinces have been affected by floods and mudslides during that time, and 3 million acres (1.2 million hectares) of agricultural land have been damaged.

This past week in Ayutthaya, north of Bangkok, Japanese automobile giant Honda Motor Co. suspended production for one week after parts factories were submerged. At least 43 factories in one of the city’s industrial zones have shut down as rising waters damaged equipment and prevented nearly 15,000 workers from accessing the plants.

The floods are proving a major test for Yingluck’s administration, which took office in July. The government has set up an emergency flood relief headquarters at the city’s Don Muang airport.

___

Associated Press writer Todd Pitman contributed to this report.