President Kibaki is set to chair a meeting of MPs allied to him in Nairobi.
At least 50 PNU MPs are at the meeting's venue, the Kenyatta International Conference Centre waiting for the President to arrive.
They have been joined by ODM rebel MPs led by Eldoret North MP William Ruto.
Among those waiting for President Kibaki's arrival are Vice President Kalonzo Musyoka, Mr Ruto and Tourism minister Najib Balala.
Earlier, the legislators had met at came at short notice Panfaric Hotel, Nairobi as the saga over the nominations to four constitutional offices raged.
The President is expected to brief the media at 3.30 pm, thirty minutes before Prime Minister's Raila Odinga scheduled address.
Last week, House Speaker Kenneth Marende declared the nominations illegal and referred the matter back to the principals to restart the process.
Mr Marende said President Kibaki did not follow the law in nominating Mr Justice Alnashir Visram to be Chief Justice, Prof Githu Muigai (Attorney General), lawyer Kioko Kilukumi (Director of Public Prosecutions) and William Kirwa as Controller of Budget.
He said the President did not consult the Prime Minister as envisaged by the constitution and the National Accord.