Two Kenyan ministers have called on the president to sack their corrupt colleagues, as the vice-president admits "massive corruption".
Following Kibaki's election, there was a high-profile campaign against corruption
Health Minister Charity Ngilu said that if corrupt ministers did not leave, the entire cabinet should be sacked.
President Mwai Kibaki was elected in 2002 on a pledge to fight corruption.
But many Kenyans and donors feel that he is no longer committed to clean up the government. On Monday, his top anti-corruption advisor resigned.
Vice-President Moody Awori admitted that "the top brass is engaged in massive corrupt activities" blocking efforts to clean up Kenya, reports the Daily Nation newspaper.
First Planning Minister Peter Anyang' Nyong'o backed up Mrs Ngilu's call.
"The president must take decisive action to save the government and the country from this ignominy," he said.
Following a meeting of European Union countries, they warned that aid could once more be suspended if corruption was not tackled.
Most donors cut off aid under former President Daniel arap Moi, citing corruption and restored funding under Mr Kibaki.
"We share the deep concern evidently felt by the Kenyan people about the lack of good governance within the government of Kenya and the damage it causes to the nation's welfare and the effective operation of its institutions," the EU members said.
On Wednesday, a colleague of resigned anti-corruption czar John Githongo told the BBC that she feared he could be in danger.
She said she had spoken briefly to Mr Githongo since his resignation and that he felt the government, and President Kibaki, was no longer committed to stopping corruption.
Mr Githongo, a veteran anti-corruption campaigner under Mr Moi, was appointed just a month after Mr Kibaki's inauguration, to oversee his fight against corruption.
John Githongo has been in the UK since his resignation
Following Mr Githongo's resignation, the US announced it was suspending funding for Kenya's anti-corruption efforts.
Last week, UK High Commissioner to Kenya Sir Edward Clay said that "massive looting" was continuing and that he knew of at least 20 dubious public contracts.
He was called an "enemy" of Kenya for his outspoken comments.
But Justice Minister Kiraitu Murungi warned diplomats not to behave as "local partisan political activists".
In apparent reference to Mr Githongo, he said: "We cannot fight corruption by running away."
A Transparency International survey of perceived corruption rated Kenya 122nd out of 133 countries in 2003.
Public hearings into Kenya's biggest ever corruption investigation, which has become known as the Goldenberg affair, have finished nearly two years after the first witness gave evidence.
The inquiry looked at how the previous Kenyan government of President Daniel arap Moi paid out hundreds of millions of dollars during the early 1990s for non-existent exports of gold and diamonds.
It is not clear when its report will be published.
Attorney-General Amos Wako said the time and money devoted to the inquiry would not be wasted; he promised to take seriously any recommendations it came up with.
During the hearings, former civil servants said they'd been ordered by Mr Moi, to pay out tens of millions of dollars as part of the fraud; the former president himself denies any wrongdoing, but did not give evidence to the inquiry.