Russia said the situation was “very tense” as flooding continued to increase in the city of Orenburg and surrounding areas.
Kremlin spokesman Dmitry Peskov warned on Wednesday that “a large amount of water is flowing into new areas.”
On Wednesday, the water level in the Ural River near Orenburg rose to more than 10 meters (33 feet), well above its breaking point, Lear news agency reported.
The floods are said to be the worst to hit the region in 80 years.
Thousands of people have been forced to flee their homes in southern Russia, and officials in neighboring Kazakhstan say the number of evacuees in the country has climbed to 97,000.
The entire village was swallowed by the flooded river.
As many as 2,000 homes in Orenburg have been flooded, and the water level has exceeded the dangerous level of 9.3 meters and is still rising. The city has a population of 550,000 and is located approximately 1,500 km (930 miles) southeast of Moscow.
“So far, the forecast is not good. The water level continues to rise,” Peskov said, adding that “massive” flooding would soon reach neighboring areas of Kurgan and Tyumen.
Peskov added that the situation “naturally requires the most strenuous efforts by government officials at all levels to help people.”
He said President Vladimir Putin had no intention of visiting the flood zone, and instead said the Russian leader was “obtaining information and coordinating the activities of all branches of the authorities.”
Last week, several rivers, including Europe's third-largest Ural River, burst their banks as rapidly melting snow and ice swelled.
The city of Orsk, about 300 kilometers (180 miles) downstream from Orenburg, was flooded after water broke through a dam embankment. Authorities currently say the situation is stable.
The Ural River flows through Orsk into Kazakhstan and then flows into the Caspian Sea.
Several regions in northern Kazakhstan are under threat of flooding, and many dams and reservoirs are full.
Regional leader Gauez Nurmukhambetov warned that a “huge stream” was headed for the city of Petropavlovsk, which has a population of 200,000.
“Let me stress again, it's huge!” he said.
President Kassym-Jomart Tokayev called on his country to unite in the face of what he said could be “the greatest disaster in terms of scale and impact in more than 80 years.”