Cuban President Raul Castro has held talks with Pope Francis, who played a key role in the breakthrough between Washington and Havana aimed at restoring US-Cuban diplomatic ties.

"Bienvenido!" Francis said on Sunday in his native Spanish, welcoming Castro in a studio near the Vatican public audience hall. The Cuban president, bowing his head, gripped Francis' hand with both of his, and the two men began their private talks.

The meeting lasted nearly an hour, a generous amount of time by Vatican standards, especially considering that the Argentine-born Francis and Castro spoke in Spanish, without the need of interpreters that often use up time in other papal VIP talks.

Notes from Havana Pope Francis may be achieving two miracles: Cuba's reconciliation with its arch enemy, the US, and with Catholicism. Raul Castro not only went to a Jesuit School, as did his brother Fidel, he also was married by a priest in a Santiago, Cuba church. But that was before the Catholic Church and leaders of the Cuban revolution fell out. Opposition to the Castros from the church led to the expulsion of hundreds of priests, the shutting down of seminaries, Catholic schools and the expropriation of some church property. Till this day the church does not have regular access to the state run media in Cuba. "Raul seems to be saying that he believes in God again. How astonishing," said a 35-year-old Cuban engineer who asked not to be named. - Lucia Newman, Al Jazeera's Latin American Editor

Castro had already publicly thanked Francis for his role in bringing Havana and Washington closer together after decades of US government policy of strict isolation of the Communist-ruled Caribbean island.

He apparently did so again during the closed-door meeting.

As he took his leave, Castro told journalists, "I thanked the pope for what he did."

Francis was in an upbeat mood, too. "I ruined your Sunday," the pope quipped to journalists after the meeting.

He gave Castro a medal depicting St Martin of Tours, known for caring for the destitute.

"With his mantle he covers the poor," Francis told Castro, saying more efforts on behalf of the poor are needed.

Francis will stop in Cuba for at least two days in September for a visit, part of a pilgrimage that will then take him to Washington, Philadelphia and New York.

Preparation for the papal's visit has already began in the Caribbean Island. Cardinal Jaime Ortega, the leader of the Catholic Church in Cuba, told Al Jazeera: "It's natural that the pope will reaffirm the church's desire for Cuba to open up to the world and the world open up to Cuba, especially as the pontiff has participated in the dialogue between the United States and Cuba."

Castro's brother, Fidel, the Cuban revolutionary leader who ruled for decades before Raul, met with Pope John Paul II at the Vatican in 1996. That Vatican encounter helped pave the way for John Paul's 1998 pilgrimage to Cuba, the first visit by a pontiff to the island.

With the Vatican keen on protecting its Catholic followers in Cuba, Francis' predecessor, Benedict XVI, also visited the island.

Castro was also due to meet Matteo Renzi, the Italian prime minister, later on Sunday before leaving Rome.