Washington  - Poor countries are increasingly threatened by the rise in food and fuel prices, which is eating up reserves and seriously endangering poverty reduction efforts, the International Monetary Fund said Tuesday.

"Some countries are really at a tipping point," IMF Managing Director Dominique Strauss-Kahn said at the release of a broad report on the crisis' economic impacts.

Food prices have doubled on average since 2006, while oil prices have quadrupled since 2003, the IMF said.

That has left a number of countries - especially in Africa - picking short-term measures to address food shortages by importing goods that severely impacted trade deficits, at the expense of longer term economic development.

"If food prices rise further and oil prices stay the same, some governments will no longer be able to feed their people and at the same time maintain stability in their economies," Strauss-Kahn said.

The higher prices have cost 33 net food importers about 0.5 per cent of their economic output since January 2007, or 2.3 billion dollars, while 59 net oil importers have had to spend about 2.2 per cent, or 35.8 billion dollars.

Crude oil has been trading at record highs of more than 140 dollars per barrel since last week. (dpa)