Kenya's political rivals were set for new talks on Friday after slow progress toward a resolution to end weeks of bloodshed as the UN's humanitarian aid coordinator arrived for a fact-finding mission.
Four people were killed overnight in tribal violence in the Kisii region of Nyanza province, two of whom were "hacked to death", said police officials.
Negotiations led by former UN chief Kofi Annan entered a crucial stage this week as the government and the opposition tackled head-on their dispute over the December presidential elections that triggered the violence.
"The topic is s crucial one, and proved divisive at times," said a joint statement from the mediation on Thursday.
"But the talks proceeded in good spirit, moving more slowly than in previous sessions, but moving steadily ahead."
Once-stable Kenya plunged into violence after elections on December 27 that President Mwai Kibaki officially won but that the opposition claims were rigged. International observers have cited serious flaws during vote-counting.
More than 1,000 people have died in ensuing riots, protests, police raids and clashes between rival tribes. Some 300,000 people have also been displaced in one of Kenya's worst crises since independence in 1963.
Nearly 50 people have been killed in violence in western Kenya this week, some of whom were shot by police cracking down on gangs who have torched houses and other property.
UN emergency relief coordinator John Holmes arrived in Nairobi for a three-day mission to assess the humanitarian crisis and was due to travel to the Rift Valley, the epicentre of the post-election violence.
Negotiators for Kibaki and opposition leader Raila Odinga opened the talks with Annan on January 29, but on Tuesday the meetings went into overdrive in a bid to come up with a settlement on the political crisis.
On Thursday, former Tanzanian president Benjamin Mkapa and former South African first lady Graca Machel returned to Nairobi to join Annan and try to bolster his mediation efforts.
Kenyan press reports said the two sides were considering a possible deal that would entail setting up a bipartisan interim government, with a mandate to enact electoral reforms and pave the way for new polls.
After meetings with all the players in Nairobi on Thursday, EU Development Commissioner Louis Michel said "there are strong signals of flexibility and open-minded attitude" and declared he was "a little bit more optimistic" about Kenya's future.
He warned however of consequences if the talks fail.
"Those who think it's possible to escape sanctions or isolation, they have to forget that and I'm speaking to all the parties," said Michel.
The United States has told eight Kenyans suspected of having a hand in the violence that they face a visa ban and other countries were considering similar measures.
The UN Security Council has expressed strong backing for Annan's mediation and urged the leaders to find a settlement.
The turmoil has delivered a crippling blow to Kenya's tourism industry, the top foreign currency earner, while tea production and agriculture have also been hard hit.
Safari resorts across Kenya and popular beach hotels in Mombasa have lost more than half of their business and the economy, which had been steaming ahead with seven percent growth, is seen as headed for a slowdown.
Kibaki's tribe, the Kikuyu, suffered heavily in the first wave of post-election violence at the hands of Odinga's Luo tribe and other ethnic groups, but there have since been numerous revenge attacks. (AFP)
Kenya crisis talks show slow progress