More than half a million people worldwide are likely to die annually by 2050 because of the impact on agriculture of changing climate, according to an Oxford University study on the future of food.

The authors say the effects are likely to be felt most acutely in south and east Asia, but that the US will also be severely affected.

They identify reduced production and consumption of fruit and vegetables as a key concern, and say the effects of climate change on agriculture could be one of its most important consequences.