There are worrying signs that the basic needs of the world's population are reaching a critical point, after food prices hit an all-time high last month.

There are also warnings that oil prices are in a danger zone which could derail global economic recovery.

UN Food and Agriculture Organisation (FAO) chief economist Abdolreza Abbassian says food prices are expected to climb even higher due to the unpredictability of current weather activity.

"Something we were expecting to be of short period is not only being prolonged, but its intensity has increased," he said.

"This certainly is a concern for an organisation like FAO where our real responsibility is to look after how the poorer countries and countries which are food insecure would have to basically deal with the situations like we have today."

Prices of foods including cereals, dairy, meat and sugar are higher than they were in 2008, when a food crisis sparked riots in Egypt, Cameroon and Haiti.

But Mr Abbassian says while in the past prices rose quickly and fell quickly, the situation has changed.

"The supply/demand structures have changed," he said.

"Certainly the kind of weather developments we have seen makes us worry a little bit more, that ... it may last much, much longer."

Though Mr Abbassian says some of the factors which caused riots of recent years are absent, including a surge in crude oil prices, this week's two-year high in oil prices is causing concern on another front.

As stocks decline and demand increases, most analysts predict prices will continue to rise this year and the impact could be felt much more widely than the local petrol station.

The International Energy Agency says oil prices could threaten economic recovery in developed nations.

The agency's chief economist, Fatih Birol, told the Financial Times newspaper "oil prices are entering a dangerous zone for the global economy and oil import bills are becoming a threat to economic recovery".