NAIROBI, Kenya — A former U.N. secretary-general, Kofi Annan, agreed yesterday to take over talks to end the deadly turmoil linked to Kenya’s presidential election, after days of international pressure resulted in nothing more than a fresh round of accusations from both sides.

The December 27 election returned President Kibaki to power for another five-year term, with his opponent, Raila Odinga, coming in a close second after a vote tally that foreign observers say was rigged. More than 500 people have been killed in the ensuing violence.

“Both sides agree that there should be an end to violence,” the African Union chairman, John Kufuor, said as he left Kenya yesterday after his two days of mediation failed even to get Messrs. Kibaki and Odinga to meet.

Mr. Annan will not arrive in Nairobi to take over the talks before January 15, his office in Geneva said. If his predecessor’s experience was any indication, Mr. Annan will have a frustrating task ahead.

Both sides continued trading blame for the political deadlock. According to the government, Mr. Kibaki “offered dialogue,” but Mr. Odinga was not responsive. Mr. Odinga, meanwhile, said Mr. Kibaki refused to sign an agreement to establish an interim coalition government and conduct an inquiry into the Electoral Commission of Kenya.

A government spokesman acknowledged Mr. Kibaki had not signed, saying he was not involved in the consultations.

Mr. Odinga has said he would meet Mr. Kibaki only in the presence of an international mediator, but Mr. Kibaki wants direct talks. Hopes for a power-sharing compromise were dampened yesterday as Mr. Kibaki’s allies were sworn in as Cabinet ministers.

Earlier, protesters from the women’s wing of Odinga’s party marched chanting “Kibaki is a thief!” Police fired tear gas at them — noting a ban on all demonstrations since the violence erupted — and the women ran away.

The European Union, America, and Britain also have been pressing for Messrs. Kibaki and Odinga to meet and added to the pressure in what Mr. Odinga’s spokesman, Salim Lone, said was a “tense meeting” yesterday with an American envoy, Jendayi Frazer, Mr. Kufuor, four former African heads of state, and the ambassadors from America, Britain, and France.

Foreign Secretary David Miliband of Britain told reporters in London that Britain has not recognized the new government, and that for that to happen, the Kenyan government would have to “clearly represent a credible expression of the will of the people.”

Kenya is crucial to the war on terrorism, having turned over dozens of people to America and Ethiopia as suspected terrorists. It also allows American forces to operate from Kenyan bases and conducts joint exercises with American troops in the region.

America is a major donor to Kenya, long seen as a stable democracy in a region that includes war-ravaged Somalia and Sudan. Aid amounts to roughly $1 billion a year, the American Embassy said.

Kenyans for Peace with Truth and Justice, an umbrella for civil groups formed after the elections, presented police with a long list of alleged charges against electoral commissioners and some staff, including forgery, subverting the rule of law, making out false certificates, and abuse of office.

The civic groups called for the prosecution of all 22 members of the commission and some of its staff, including vote-counters. The commission’s chairman, Samuel Kivuiti, pronounced Mr. Kibaki the winner, then later said he wasn’t sure the results were accurate.