The announcement comes even as a lobby group filed a petition at the High Court on Wednesday seeking to stop the appointment.
The Consumer Federation of Kenya (Cofek) secretary-general, Stephen Mutoro, said the action was not linked to increased speculation that the board had settled on an insider to take over the mantle from Michael Waweru.
“We have no idea who they have settled for. All the applicants are qualified enough, but we are faulting the process,” said Mr Mutoro on Wednesday.
The battle for Waweru's succession was expected to be between Mr Njiraini, the man who topped during interviews for the Controller of Budget, and Barclays Bank Kenya CEO Adan Mohamed.
Customs Department Commissioner Wambui Namu was the other top contender.
Others shortlisted for the position were KRA commissioner for Domestic Taxes Alice Owuor and support services head Helen Bila.
Besides Mr Mohamed, other applicants from outside the authority were James R. Njuguna and African Development Bank chief James Gituro Wahome.
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Note: The results are not exact but very close to the actual.
