Markets watch Russia for possible grain export controls
8 August 2012 Last updated at 13:18 BST
Traders are watching Russia where a newly-formed commission on food security is meeting in response to dry weather that has halved grain yields in some areas.
There is market talk that Russia might respond by limiting or stopping exports - as it did two years ago - increasing already high prices.
With the United States already facing its worst drought for 50 years, prices of many grains and food crops have soared on world commodity markets.
The BBC's Nigel Cassidy reports.