The crisis was widely predicted after last year's poor harvests, following poor rains and locust invasions.

"The world wakes up when we see images on the TV and when we see children dying," Mr Egeland told the BBC's World Today programme. [...]

"The funding needs are sky-rocketing because it's a matter of saving lives," UN World Food Programme Niger representative Gian Carlo Cirri said.

"The pity is we designed a preventative strategy early enough, but we didn't have the chance to implement it." [...]

Mr Egeland said it would have cost $1 a day to prevent children becoming malnourished but it was now costing $80 a day to save a child's life.

Aid workers in Niger say that up to a quarter of Niger's 12 million people need food aid.

The UN has now received just a third of the $30m it had asked for, Mr Egeland said. [...]

He said the $30m requested for both short - and long-term aid "was nothing".

"Europeans eat ice cream for $10bn a year and Americans spend $35bn on their pets each year."