A flight carrying British aid has arrived in Niger, west Africa, where millions face starvation after drought and a plague of locusts.
Hundreds of thousands of children could die in the famine
A British Red Cross team will distribute food, seeds, medical equipment and other essential items.
The Red Cross said up to 2.5m people urgently needed food, and one in 10 children could die unless helped.
It is trying to raise £8m worldwide. The UK government has announced a total contribution of £3m.
Miranda Bradley, part of the Red Cross team, said the crisis could be the worst famine in Africa for more than a decade.
Team leader Peter Pierce said: "Our main function will be to receive, store and forward on all the relief items that will be arriving.
"It's difficult to know what to expect and we will undoubtedly face challenges but it is vital that we transport everything off the planes and to people in need as fast as possible."
The charity launched an appeal after the drought and plague of locusts left eight million facing famine in Niger, Mali, Mauritania and Burkina Faso.
The Red Cross appeal, launched on Friday, aims to raise £8m globally, with £500,000 coming from Britain.
They will transport vehicles and technical equipment so that they can distribute aid once it arrives.
Children at risk
Ms Bradley, 31, said the logistics of taking food across Niger could be difficult because it is the wet season.
"We are there to set up the tracking and communication systems so we can distribute the aid, which will mainly be food around the country," she said.
Oxfam has also launched a £1.4m appeal to help 130,000 people in Niger with a food voucher scheme.
Natasha Kafoworola Quist, the charity's regional director for West Africa, said the lack of food had pushed prices beyond the means of most families.
"Families are feeding their children grass and leaves from the trees to keep them alive," she said.
On Saturday the United Nations' relief chief said aid had finally begun to arrive in Niger, but only after graphic pictures of starving children were broadcast last week.
Appeals in November, March and May had failed to generate enough aid, Jan Egeland said.
He added: "It took the images of children dying to make the world wake up. We should not have had so many children dying in Niger."
The UN's Office for the Co-ordination of Humanitarian Affairs said £1.6m was donated last week, bringing the total to $2.2m.
The amount is still a fraction of the £17.6m it wants to help the starving in Niger, where aid workers say a quarter of the 12m population need aid.
A second aid flight from the UK is due to leave for Niger on Wednesday.