Rising water from the Mississippi River has flooded several towns in the state and ruined cropland.

Volunteers and National Guard troops helped raise levees on both sides of the river seeking to protect low-lying businesses, water supplies, and prime farmland planted with increasingly valuable crops.

Corn and soybean prices closed near record highs after millions of acres of US cropland were lost or damaged in the heart of the world's largest grain exporter.

Cattle and hog prices also hit new highs, with soaring feed costs expected to prompt farmers to cull livestock numbers.

US President George W Bush promised aid to the stricken region, where farm and business losses are expected to be in the billions of dollars.

He said: "I fully understand people are upset when they lose their home. A person's home is their most valued possession. We want to work with state and local folks to have a clear strategy to help people get back into a place where they can live."

His comments come three years after he was heavily criticised for the administration's slow response to Hurricane Katrina in New Orleans.

Meanwhile, hundreds of National Guard troops and volunteers have joined in sandbagging efforts across the Midwest.

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