A major corruption scandal in Kenya is threatening to topple the very government that promised to rid the country of its corrupt past. BBC East Africa correspondent Karen Allen looks at the storm surrounding the "Githongo dossier".
President Kibaki faces tough decisions ahead of polls due next year
When President Mwai Kibaki was elected in December 2002, ending 25 years of rule by Daniel arap Moi, he promised voters that "corruption will now cease to be a way of life in Kenya".
But the euphoria of the first year in power has given way to despair with allegations that President Kibaki's own government is involved in a multi-million dollar scam linked to bogus security contracts, known as the Anglo Leasing affair.
The allegations - which Mr Kibaki apparently knew about more than a year ago - came in an explosive report by John Githongo, the man who was appointed by the president himself to help expose dodgy deals.
One minister has already resigned and there is now pressure for more to go, including Vice-President Moody Awori, who stands accused of misleading parliament over the scandal.
He, however, says he has no intention of leaving office.
"I honestly and sincerely see no reason to step down. I am not resigning. I have committed no crime. Who is my accuser? On what charge? How am I impeding investigations?" he said.
Many fear that with those accused still in their jobs, investigations cannot be independent - and in Nairobi, everyone on the street is talking about the "Githongo dossier".
The BBC has a copy of his extraordinary report and a covering letter sent to the president in November.
It alleges former and current ministers have been involved in a series of dubious deals costing millions of dollars in public money.
One month later, the president reappointed three out of the four ministers named.
"Dear Sir", the letter begins, "please find enclosed a summary document on my findings regarding the most egregious cases of corruption that were the subject of my attention under your instruction."
Mr Githongo says he has "evidence of culpability on the part of the senior-most officials of our administration".
The letter explains that Mr Githongo kept a record of key meetings he was involved in, and recounts efforts by senior ministers to try and get him to go easy in his investigations into the corruption scam.
He accuses senior figures in the cabinet of lying to investigators and to parliament and alleges that the finance minister, who resigned earlier this week, knew that the dodgy deals were linked to characters from the Kenyan business world whose previous activities had aroused suspicion.
But perhaps the most damning element in his report is the claim that the president was told what was going on as long ago as October 2004.
"Clearly from all the circumstantial evidence and from what I had been told by some of the perpetrators themselves and as the president had acknowledged to me on several occasions, we had a major graft problem and it was being perpetrated by characters within our administration."
Mr Githongo is now in exile in Britain after receiving death threats at home.
The cabinet is split on how to react to the crisis. President Kibaki, who received the dossier last November, has remained conspicuously silent.
"To the extent that he's not done anything since November, I think one can safely say that he cannot escape blame for this Anglo Leasing fiasco," argues Wangethi Mwangi, editorial director of the Nation newspaper which broke the corruption story.
Vice-President Awori sees no reason to leave office
The vice-president's announcement that he won't step down, will be interpreted as an attempt to stand up to international criticism.
The World Bank has put a $260 million aid package to Kenya on hold - in response, Mr Awori questioned whether foreign donors would treat their own officials with similar suspicion.
However much Kenya would like foreign donors to keep out of its affairs, the Anglo Leasing scam appears to have an international dimension.
In Britain the Serious Fraud Office is investigating addresses linked to the scam.
An international investigation needs to be reopened since this may provide more clues to where the money went, believes Maina Kiai of Kenya's Human Rights Commission.
"That's where the meat is - that's where a lot of stuff is and that's where we can get investigations with integrity," he says.
"So I think there's a lot of room and a lot of space for us to pursue and prod and push until we get to the truth".
The scandal leaves Kenya at a crossroads. The government which swept to power on an anti-corruption ticket is in crisis.
In a country where the president is all-powerful, President Kibaki needs to act decisively if his government is to survive until elections due next year.