The worst drought in the US for 50 years is raising fears of a food crisis.

The price of corn and soyabeans reached record highs on Thursday as supplies continue to be hit by the blistering heat.

There is little or no rain forecast until at least the end of this month.

The US is the world's biggest producer of corn and a major supplier of wheat and soyabeans.

Nik Higgins from Rabobank warns there is a real risk of food riots.