Here in Mali, families are trapped in a perfect storm - the consequences of climate change and political regime change. Drought has led to a dreadful harvest and rocketing prices, whilst the departure of Gaddafi has led to migrating mercenaries, laden with arms.

Not only has nature shrivelled the crops, but the population in the North has had to flee the fields, leaving the land unplanted.

In the best of times, over a quarter of Malian children are malnourished: the October harvest typically runs out by June, leaving four months of hunger. But this is different. "The worst harvest that I have seen in my lifetime," says Chief Noriba Doumbia when I visit his village of Nienguen. Here, a farmer like Cheickna normally grows five tons of maize and two tons of millet. This year however, there's no maize, just 100 kilos of millet. I found Cheickna asking neighbours to help feed his five children.

Nationwide, five million people - the majority, children and nursing mothers - are acutely affected. The harvest is down 41%. Families have less than half their normal food stores and staples like millet and maize and peanuts (provider of sauce and protein) have doubled in price. For a widow such as 30 year-old Sara, living in an area where women traditionally do not own land, it is a struggle to feed her seven children, and she relies on the sale of firewood and the aid of neighbours. She says, "However now, those who used to give me food have not got enough for themselves."

Tounkara, a worker for Plan Mali, includes Sara in Plan's emergency food distribution - a sack of rice, plus milk and salt and palm oil, which will last a month for her family. Between July and September, Plan Mali will focus on four of the worst-hit border areas, targeting malnourished children with food supplements and providing food for the under-5s as well as for pregnant and breastfeeding mothers.

In the northern regions of Mali some 2.2 million people find themselves living in a conflict zone, with newly-armed Touaregs fighting for an independent homeland and Islamic groups attacking a state which has a government recently overthrown by a coup. This has caused 300,000 to flee to neighbouring countries and 150,000 into the south of Mali.

The cultural traditions of supporting the extended family mean that 95% are living with host families. Every Plan Mali staff member is supporting relatives, be it by sending food or offering open house.

I met 79 children evacuated from a children's home in Mopti (on the border) to safety in Sanankoroba (35km from Bamoko). They spoke of seeing planes from their garden and constantly fearing attack and worrying about those left behind. Plan provided supplies of food (cereal, oil, salt, milk) and household goods (bowls, soap, toothpaste) for these children and their carer s.

Plan is also supporting 86 families who fled the fighting and now live in a former training centre. Christine Coulibaly fled Timbuktu with her four-month old baby, leaving her husband behind. "I managed to get the last seat on the bus." Hawa walked with her husband and seven children - the youngest aged 11 - each carrying one water pot and a change of clothes. "The rebels were coming - we saw they would smash everything. My children still have nightmares."

Plan is starting a children's centre so that the young have somewhere to play and get over their fears in the camp for displaced people. Plan is also working with the Education Ministry to provide remedial classes and delayed exams for those who have missed school. In addition, it is supplying 'dignity kits' for men and women left with almost nothing; contents range from sanitary towels and headscarves to shaving stuff and toiletries. And a mosquito net for everyone.

A snapshot survey by Plan and other NGOs has shown how families are coping. A quarter said parents had left to find work; a quarter had sent children out of the area; half were having fewer meals; three-quarters said children had given up school in hope of work - the girls as maids in the cities, the boys by panning for gold.

For the future, Plan is teaching villagers how to cope with unreliable rainfall by building water tanks; by harvesting it in ponds; by growing drought-resistant crops; and by building more village granaries.

But it is worth reflecting upon British responsibility in this unfolding tragedy. Amidst all the governmental self-congratulation on the Libyan liberation, no heed was paid to history's lesson that demilitarisation should follow a civil war. And the Western arms so generously spread among Malian mercenaries have travelled south to destabilise a second country. Perhaps some governmental gold-dust should now be sprinkled upon Mali?

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