Leaders from Benin, Cape Verde, Sierra Leone and Kenya were also expected to offer President Laurent Gbagbo amnesty if he quits, the BBC reported.
The United Nations and the African Union regard Gbagbo's rival, Alassane Ouattara, the winner of the Nov. 28 presidential election. But Gbagbo alleged election fraud and refused to step down.
The heads of state who are to meet with Gbagbo represent the Economic Community of West African States. It is their second visit in less than a week. Tuesday they flew to Abidjan, Ivory Coast's capital, but failed to convince Gbagbo to cede power.
Sierra Leone Information Minister Ibrahim Ben-Kargbo said the leaders would tell Gbagbo to step down and didn't intend to negotiate with him.
The United Nations said some 200 people -- mostly supporters of Ouattara -- have been killed or have disappeared in the past month.
U.N. peacekeepers in the country said Ivorian security forces twice blocked them from visiting the site of one of two alleged mass graves.
The election was intended to reunify Ivory Coast. Ouattara was initially proclaimed the winner by the country's election commission, a verdict backed by the United Nations.