The agreement between Kibaki and Odinga was struck last week, after weeks of mediation by Kofi Annan, the former UN secretary-general.
Both sides have agreed to set up a committee that will outline policies for the coalition government to be formed in the coming days.
The power-sharing agreement broke a two-month old deadlock created by the disputed presidential elections, held in December 2007.
The newly formed cabinet coalition will replace the previous government announced by Kibaki, days after he was controversially declared the winner of the presidential polls.
Earlier, Kenya's 10th parliament was opened on January 15 at the height of political violence and tribal killings that had left around 1,500 dead.
It is only after weeks of mediation that Kibaki and Odinga struck a deal on February 28.
Last month's accord had been well received in Kenya but tough negotiations lie ahead for both sides as the government line-up remains yet to be decided.
Kibaki had invited Odinga then to join his government but the opposition leader refused to recognise Kibaki's re-election, plunging Kenya into its worst ever political crisis.
Nationwide clashes between Odinga and Kibaki's supporters had triggered a wave of ethnic violence across Kenya.