Kofi Annan brokered a power-sharing deal following two months of violence
The names of key suspects involved in violence after the 2007 Kenyan election have been handed to the International Criminal Court (ICC).
Mediator Kofi Annan said he had handed the names in a sealed envelope to the prosecutor in The Hague.
At least 1,500 people were killed and 300,000 displaced in two months of violence after the December 2007 polls.
The BBC's Caroline Karobia in Nairobi says Mr Annan is trying to put pressure on Kenyan leaders to set up a tribunal.
A week ago, Kenyan ministers promised to establish the tribunal by July 2010 and in the meantime provide the ICC with the details of their investigations.
Their move came a month after Mr Annan gave Kenya an August deadline to establish the special tribunal, warning that he would hand over the list to the ICC if the deadline was not met.
The violence broke out after supporters of then-opposition leader Raila Odinga said he had been cheated of victory.
The election crisis ignited long-standing ethnic rivalries over access to land and other economic resources, and some 300,000 people were forced to flee their homes.
After two months of violence, Mr Annan brokered a deal for Mr Odinga to join a power-sharing government as prime minister with President Mwai Kibaki.
In a statement from Geneva, Mr Annan said he welcomed Kenya's efforts to establish a special tribunal.
But added that any mechanism "must meet international legal standards and be broadly debated with all sectors of the Kenyan society" to give it credibility.
Mr Annan said: "Justice delayed is justice denied.
"The people of Kenya want to see concrete progress on impunity. Without such progress, the reconciliation between ethnic groups and the long-term stability of Kenya is in jeopardy."