NAIROBI, Kenya (CNN) -- Kenya's opposition party struck a significant blow against the government as its candidates were elected as the house speaker of parliament and deputy speaker in the third round of voting Tuesday.
Kenneth Marende was elected in a 105-101 vote over the government candidate, Francis Ole Kaparo, who had been speaker since 1993.
Farah Maalim, also a member of the opposition Orange Democratic Movement, was elected deputy speaker.
The parliamentary votes mark a significant win for opposition leader Raila Odinga.
It was the first session of the parliament since last month's disputed and deadly presidential elections -- and the first time President Mwai Kibaki and Odinga had been in the same room since votes were cast.
Kibaki's party members arrived hours before the session began, in part to prevent Odinga's Orange Democratic Movement members from taking their benches.
Odinga had earlier said he would sit on the government side of parliament because his party won more seats in the parliamentary elections. He took a spot in the opposition leader's side, and refused to look at Kibaki as the president entered the chambers.
The United States ambassador was also present to observe the proceedings.
The government tightened security around the parliament building and began shuttling in truckloads of riot police, CNN's Zain Verjee reported.
All major roads leading to the building were blocked and barricaded, and soldiers were deployed along thoroughfares.
Odinga's party won 99 seats in the 222-seat legislature, while Kibaki's secured 43. Based on that, Odinga had earlier said he would station himself on the government side of the chamber.
"The standing orders are very clear," Odinga said. "They say the majority party is the government party. We are the majority party, and therefore we are going to be sitting on the government side, because we expect the minority party to sit on the opposition benches."
The speaker's election required a two-thirds majority for the first two rounds and a simple majority in the voting reaches a third round, said analyst Macharia Munene, an international relations professor at Nairobi's United States International University.
More than 600 people died in a widespread and ethnically motivated killing spree after Odinga accused Kibaki of rigging the December 27 vote to win his re-election.
Supporters of Kibaki, a member of the Kikuyu tribe, battled with machetes on the streets with supporters of Odinga, a member of the Luo tribe. And Kenya, long one of the most stable and economically developed nations in East Africa, descended into chaos.
Odinga said that, despite all the violence, he would be prepared in a new government to work with, but not under, Kibaki. He called on the president to negotiate on power-sharing and to set a date for new elections.
Former U.N. Secretary-General Kofi Annan was expected to arrive Tuesday night to take over mediation efforts in the dispute.
However, he has had to postpone the effort for a couple of days because he "was taken ill with a severe flu" on his way to the airport in Geneva.
"Mr. Annan very much regrets this delay but he is in touch with other members of the panel of eminent African personalities. The team will proceed to Nairobi as soon as feasible," Annan's office said. E-mail to a friend
CNN's Saeed Ahmed and Zain Verjee contributed to this report.