Jimmy Carter meets Cuban President Raul Castro
Former US President Jimmy Carter has held private talks in Havana with Cuban leader Raul Castro.
Earlier, Mr Carter said he had raised the case of imprisoned US contractor Alan Gross with Cuban officials.
But he said he had not come to Cuba to secure the release of Mr Gross, whose case has raised tensions between Washington and Havana.
On Wednesday Mr Carter is expected to meet some of Cuba's most prominent dissidents.
The US aid contractor Alan Gross was jailed earlier this month for providing satellite communications equipment to Jewish groups in Havana.
There had been speculation that Mr Carter would be seeking his release when his three-day visit to the Communist-run island was announced last Friday.
But he said the case was not the main motivation for his trip.
"I am not here to take him out of the country," Mr Carter said.
"We are here to visit the Cubans, the heads of government and private citizens".
"I hope we will be able to contribute to better relations between the two countries," he added.
Since arriving on Monday, Mr Carter has met Cuban government officials and religious leaders, including the Roman Catholic Cardinal Jaime Ortega.
Several prominent Cuban dissidents, including internet blogger Yoani Sanchez, said they had been invited to meet the former US president on Wednesday.
Mr Carter, 86, is the only sitting - or former - US president to have visited the Communist state since Raul Castro's brother Fidel took power in the 1959 revolution.
He has visited the island before, in 2002, when he urged the US to lift its trade embargo against Cuba. He also called on the Cuban authorities to introduce democracy and improve human rights.
Alan Gross was sentenced to 15 years in prison by a Cuban court after a brief trial.
He was working for Development Alternatives, a US contractor, under a programme funded by the US State Department.
The Cuban authorities say the satellite equipment was intended to provide dissidents with access to the internet as part of efforts to destabilise the island.
The US administration has said there can be no further major US initiatives to ease relations with Cuba while Mr Gross remains in jail.