Washington - US President Barack Obama on Saturday pledged continuing national support to victims of severe flooding in North Dakota and neighbouring Minnesota and South Dakota.

In his weekly radio address, Obama also praised the thousands of volunteers who have filled sandbags to fight the rising waters.

"Even as we face an economic crisis which demands our constant = focus, forces of nature can also intervene in ways that create other crises to which we must respond - and respond urgently," he said. "For the people of North and South Dakota and Minnesota who live along rivers spilling over their banks, this is one such moment."

More than 10,000 residents of North Dakota's largest metropolitan area evacuated Friday as the Red River roared to its highest ever level and a crack appeared on a crucial sandbag dike.

The Red River, which runs from Canada through Minnesota and North Dakota, is expected to crest at 12.8 metres near Fargo on Saturday, topping many of the dikes designed to protect the Fargo-Moorhead metropolitan area and its total population of 343,000.

Obama said federal officials were working with governors in each state to offer assistance. The Department of Homeland Security and the Federal Emergency Management Agency were coordinating Washington's response. (dpa)