Corruption has blighted the image of east Africa's biggest economy for decades and many Kenyans view efforts to stamp it out as bogus and ineffective.

 Githu Muigai, Kenya's attorney general, said four territories had agreed to cooperate - Switzerland, Japan, the United Kingdom and Jersey, a British dependency known for its offshore banking.

"The assistance we requested from those governments includes giving us information, giving us materials and allowing us access to court documents where some cases have taken place," Muigai told a bankers' conference in the port city of Mombasa.

"It is going well and we hope that by the end of the year, we will start receiving some money where there is no contest as to whether that money ought to be returned to Kenya," he said.

Muigai said two countries had been asked for help but had not yet committed themselves. He declined to name them.

Analysts say graft has choked growth in Kenya, deterring potential investors. There is growing frustration that senior officials get away with flagrant theft.

One graft scandal, Goldenberg, which took place during the leadership of former President Daniel Arap Moi, led to the loss of at least $1 billion in central bank money via compensation payments for bogus gold and diamond exports.