"We have come to an understanding on the coalition agreement," Annan told reporters after meeting President Mwai Kibaki, opposition leader Raila Odinga and African Union head Jakaya Kikwete. Annan said he would give details at 1300 GMT.
Thursday's talks brought Odinga and Kibaki to the same table for the first time in a month, after discussions between negotiators for the two men hit a deadlock earlier in the week.
"We've had a very constructive and fruitful day and we've come to an understanding on the coalition agreement ... I'm not in a position to tell you anything further, all that I can say is we do have an agreement," Annan said.
Odinga and Kibaki have come under intense pressure to compromise over Kibaki's disputed re-election in a Dec. 27 vote, which sparked ethnic violence that killed 1,000 people and displaced 300,000 more.
The opposition had threatened to hold mass street protests on Thursday, but called them off after meeting Annan, a former U.N. Secretary-General, on Wednesday.
Kibaki has agreed to create a prime minister post, as demanded by the opposition, but it was unclear what powers a premier would have and how many cabinet jobs Odinga's side would get.
The crisis that exploded after Kibaki was sworn in on Dec. 30, amid Odinga's claims the election was rigged, seriously hurt Kenya's reputation as a stable, prosperous nation in a turbulent corner of Africa.
Güncelleme Tarihi: 28 Şubat 2008, 17:32