Kenya's state-run broadcaster is biased in favour of President Mwai Kibaki in its coverage of this month's elections, the electoral commission says.
President Kibaki is trailing in opinion polls
Samuel Kivuitu condemned the Kenya Broadcasting Corporation (KBC) for not providing equal coverage to all presidential candidates.
Meanwhile, Mr Kivuitu said local polls may be delayed in some areas after faulty ballot papers were supplied.
Mr Kibaki faces a strong challenge from Raila Odinga in the 27 December poll.
"KBC has let us down as tax payers," Mr Kivuitu said.
"In an election year reporting should show competition, it cannot be that others are so stupid that they have nothing which can not be reported."
Officials at KBC have not responded to the accusations.
Mr Kivuitu said the broadcaster had breached the election code of conduct that required the media to provide equal coverage to all presidential candidates.
The electoral commission has taken up the matter with KBC and expected the imbalance will be corrected within the remaining 13 days before the election.
Mr Kivuitu also revealed that local elections may not be held on time in several wards after errors were discovered on the printed ballot papers.
He said most of the affected candidates had been assigned the wrong parties.
"This is serious and can affect the outcome, so we shall consider the ballot papers invalid," Mr Kivuitu explained, without revealing the names of affected constituencies.
He, however, said the printers in UK had promised to make changes and deliver the ballot papers in time for the elections.