NAIROBI, Kenya (CNN) -- Kenyan President Mwai Kibaki appeared to offer a way out of a stalemate with the opposition over disputed elections, announcing Saturday he was ready to form a government of national unity, a government spokesman said.
Internally displaced Kenyans gather at St. John's cathedral in Eldoret, Kenya, on Friday.
Opposition leader Raila Odinga immediately responded to the announcement, telling a press conference that he was ready to negotiate with the president without preconditions.
Odinga's Orange Democratic Movement (ODM) had earlier insisted Kibaki must resign before talks could take place.
The apparent olive branch came as new figures revealed the humanitarian cost of a week-long spate of violence.
According to the United Nations, some 250,000 Kenyans are now estimated to have been displaced by rioting and looting that accompanied the result of the Dec. 27 election.
The U.N. said that in total, between 400,000 and 500,000 people had been affected by the unrest. Around 300 people are reported to have died. Watch a report from the front lines »
The humanitarian crisis came after rioters went on the rampage following Kibaki's narrow victory, which was disputed by Odinga's party. The ODM accused the president of election fraud.
The violence that has plagued Kenya in the last week appeared to have abated Saturday, with CNN's Kim Norgaard saying Nairobi was quiet as inhabitants went about their normal business.
In the western town of Kisumu, the scene of some of the worst unrest, the police lifted a curfew imposed earlier this week, aid workers in the town told CNN.
Kenyan police said that more than 1,000 arrests had been made in connection with post-election unrest.
In a statement released Saturday police said that 451 of those arrested had already been charged and a further 70 are still in police custody.
The charges are for offenses including arson, unlawful assembly, robbery and murder, the statement said. The highest number of arrests took place in the coastal region, it added.
The offer of a unity government followed talks Saturday between the Kenyan president and U.S. diplomat Jendayi Frazer, who flew in a day earlier to try to broker a solution to the crisis.
Alfred Mutua, the Kenyan government spokesman, did not say if the offer meant the president was prepared to enter into a power-sharing arrangement with Odinga.
Mutua said the president was ready to work with "like minded parties."
"We do want a strong opposition, otherwise we would have a one-party state," Mutua added.
Reacting to the news, Odinga told a press conference that he would be happy to sit down and negotiate with Kibaki.
Pressed by CNN as to whether he would willingly serve in a coalition government with the incumbent leader, he said it was a matter for the negotiating table.
The Kenyan Red Cross, meanwhile, is appealing for $15.4 billion in aid for those forced from their homes by the crisis.
Kenyan Red Cross spokesman Anthony Mwangi said the biggest concern was getting food to those in remote areas.
The World Food Program said it would shortly provide food through the Kenya Red Cross for 100,000 people displaced in the northern Rift Valley.
The U.N. food agency said the movement of food through western Kenya and the rest of the region -- including Uganda, Sudan and the Democratic Republic of the Congo (DRC) -- ground to a halt for days due to the unrest. E-mail to a friend
CNN's Kim Norgaard and Paula Newton in Nairobi contributed to this report.
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