Two Kenyan ministers linked to separate corruption allegations have resigned.
Kiraitu Murungi has denied any wrongdoing
President Mwai Kibaki announced the resignations of Energy Minister Kiraitu Murungi and George Saitoti who held the education portfolio in a TV address.
Mr Murungi vowed to stay on last week after the BBC obtained a tape allegedly of him trying to block an inquiry.
Also last week, an enquiry into an alleged $600m fraud under the previous government said Mr Saitoti should be investigated. Both deny any wrongdoing.
Mr Kibaki came to power in 2002, pledging to fight corruption.
In his televised national address, he said the pair were stepping down to allow investigations into the allegations against them to proceed smoothly.
"I urge all Kenyans to exercise patience as the relevant arms of government carry out investigations into these issues," Mr Kibaki said.
The two men have been implicated in separate large-scale scandals that have undermined public faith in Mr Kibaki's administration.
Mr Murungi, previously justice minister, was alleged to have been recorded asking John Githongo, Kenya's former chief anti-corruption investigator, to slow down a corruption inquiry.
The affair, which has become known as the Anglo Leasing scandal, prompted a delegation of Kenyan MPs to fly to the UK, where Mr Githongo is in exile, to quiz him about his allegations.
The scandal may undermine President Kibaki's administration
Mr Githongo said he was "reassured" after meeting MPs over the weekend.
David Mwiraria resigned as finance minister at the start of February after being implicated in the scandal, in which contracts were awarded to a company that existed in name only.
Mr Saitoti stood down as education minister because of allegations of involvement in the country's biggest corruption scandal.
The so-called "Goldenberg affair" pre-dates Mr Kibaki's administration, and involved huge sums of public money in a bogus gold and diamond export operation.
The BBC's Adam Mynott in Nairobi says many other officials have been accused in both scandals.
He says pressure is bound to continue for more heads to roll.