"KIBAKI LACKS LEGITIMACY"
Odinga, who turned 63 on Monday, is under international pressure to avoid provoking more violence, but he also wants to maintain momentum to oust Kibaki.
Kibaki's government accuses Odinga's Orange Democratic Movement (ODM) of "grandstanding" and stoking further unrest.
Adding to the chaos, the main Kenyan lawyers' organisation, the Law Society of Kenya (LSK), accused electoral officials of "dishonesty and ineptitude", called Kibaki's swearing-in "null and void", and urged a fresh vote.
"Kibaki lacks legitimacy to govern and this is the cause of the problems that we are facing as a country," it said.
Government spokesman Alfred Mutua said the statement was inaccurate, misleading and confusing to the public.
"LSK should not be partisan and should exercise responsibility by refraining from making claims based on events where they were not present, have no idea of what occurred and at what time," Mutua said.
Kenyans say mutual distrust between Odinga and Kibaki is a major obstacle to any solution.
Kibaki has said he is ready to form "a government of national unity". But Odinga wants him to step down and hold internationally mediated talks to agree on a "transitional arrangement" before a new vote in three to six months.
Around the country of 36 million people, the poor in city slums and rural areas have been worst hit. The political elite, other affluent Kenyans and expatriates have been largely unaffected in guarded compounds.
Kibaki met six bishops from the worst affected area -- Rift Valley -- on Monday to explore ways to end the unrest.
The election dispute unleashed protests, riots and anarchy that have scattered refugees across a nation more used to helping those fleeing from countries like Sudan and Somalia.
Eleven U.N. trucks were heading to western Kenya, the heart of the refugee crisis, under police escort on Monday, with enough food to feed 38,000 people for two weeks.
Much of the trouble has pitched opposition supporters against members of Kibaki's Kikuyu tribe, including the massacre of about 30 people sheltering in a church near Eldoret, a western town with decades-old land tensions.
