The UK is to give drought-stricken Kenya an extra £15m in humanitarian assistance, International Development Secretary Hilary Benn has announced.
Mr Benn is urging the international community to contribute quickly
Around 11 million people are in serious danger in Kenya, Ethiopia, Eritrea, Somalia and Djibouti, the UN estimates.
The situation has prompted the UN and the Kenyan Government to launch a £130m appeal for emergency aid.
The UK cash includes £10m for the World Food Programme to help 223,000 of the most vulnerable people for six months.
It also covers £2m for a larger UNICEF programme to provide emergency feeding for 73,000 malnourished children under five, and 7,200 pregnant and nursing mothers, plus healthcare for more than 460,000 children.
Mr Benn said he hoped the international community would "contribute quickly" to help save the lives of those at risk.
"The drought in Kenya and across the horn of Africa is having a terrible effect," he said.
"The increased UK contribution will help to provide food and emergency healthcare to the areas that desperately need it."
Up to 3.5m people are thought to be at risk from the food crisis which has hit the Horn of Africa, with Kenya under particular threat.
A total of £21.7m has been given to Kenya by the UK in response to the drought since December 2005.