A day after his government ordered troops to the affected areas to distribute food and water, Kibaki said he was allocating $US40 million dollars to relieve the crisis.
But he added that $US100 million more would be needed.
"To meet this gap, I am therefore appealing to the Kenyan public and
development partners to come forward and make a contribution to this noble cause," he said.
"As we celebrate Christmas, let us remember those of our people who are experiencing food and water shortages," Kibaki said.
He said that 7.5 million bags of maize and 2.5 million bags of beans were being sent to affected districts but that "the population in need continues to increase due to the rapidly worsening conditions."
He said money was required to buy and distribute supplies of staple foods as well as powdered milk, nutritional supplements and livestock fodder.
Kenya's Special Programmes Minister John Munyes announced on Friday that the military had been deployed to assist in relief operations in 17 districts.
But he downplayed claims by local politicians that the situation was spiralling out of control and that 12 people had already died from starvation.
Nairobi's two leading newspapers have accused the government of being slow to respond to deteriorating conditions.