The restrictions reduced supply on international markets, helping to drive prices even higher.
Grain markets have been boosted recently by speculation that Black Sea grain producers, particularly Russia, might impose export restrictions after a drought there hit crops.
Markets drew a little comfort from official Russian comments on Wednesday that the country saw no grounds to ban grain exports this year but did not rule out protective export tariffs after the end of the 2012 calendar year.
The FAO Food Price Index, which measures monthly price changes for a food basket of cereals, oilseeds, dairy, meat and sugar, averaged 213 points in July, up 6 per cent from 201 points in June, the FAO said in its monthly index update.
The rise, which followed three months of declines, was driven mainly by a surge in grain and sugar prices, while meat and dairy prices were little changed, the FAO said.
It said the US drought, which is the worst to hit the Midwest in 56 years, had pushed up corn prices by almost 23 per cent in July, and international wheat prices had followed, rising about 19 per cent amid worsening output prospects.
Although below a peak of 238 points in February 2011, when high food prices helped drive the Arab Spring uprisings in the Middle East and North Africa, the index is still higher now than during the food price crisis in 2007/08.
Higher food prices mean higher import bills for the poorest countries, which do not produce enough food domestically, and a strong dollar would deepen that impact.
"The very strong appreciation of the dollar, and the surge in prices, is basically a double blow which is going to be quite stressful for some of the more fragile countries," Abbassian said.
Charity Oxfam said that the surge in prices could drag millions of people around the world into conditions of hunger and malnourishment, in addition to nearly one billion who are already too poor to feed themselves.
"These price hikes are being driven by more than just a drought in the US corn-belt and problem harvests elsewhere. Our food system should be more resilient than this," Oxfam spokesman Colin Roche said in a statement.
Roche said governments needed to invest more in smallholder farmers, reconsider biofuel policies and make more effort to tackle climate change.
The FAO's Abbassian said the situation was still quite different from 2007/08, when crude oil prices were at record levels, adding to farmers' costs.
Abundant supplies of rice and sluggish economic growth should also ease the upward pressure on prices, but a lot will depend on how the weather develops for US crops and how demand develops in coming months, he said.
"We will have to see how the high price will ration demand, and to what extent, be it lesser exports or lesser use for biofuels," Abbassian said.
"What is quite certain is that it is not going to be a season where prices fall below the previous year, which is what we had anticipated. It is going to be another season of very high prices."
Source: Reuters
