Havana, Cuba (CNN) -- A member of the "Cuban Five" spy group renounced his United States citizenship at the U.S. diplomatic mission in Havana on Monday, removing the final obstacle to his permanent return to the island.
Rene Gonzalez, a Cuban intelligence officer, was a member of a network of agents in South Florida that the Cuban government said was gathering intelligence to prevent terrorist attacks against Cuba; U.S. federal prosecutors called them a dangerous spy cell.
The men were convicted in 2001, and ever since they have been the focus of a campaign by Cuban officials to free them.
Gonzalez was released from prison in October 2011 but was required to serve three years' probation in the United States.
But on Friday U.S. District Judge Joan Lenard ruled that Gonzalez, who had already been allowed to temporarily return to Cuba for his father's funeral, could stay there if he renounced his U.S. citizenship.
In her ruling she wrote that federal prosecutors had said Gonzalez would be less of security risk to the United States if he returned to Cuba. Previously prosecutors had argued that Gonzalez should not be allowed to return to Cuba.
Gonzalez, who had dual Cuban and American citizenship, arrived Monday at the U.S. Interest Section in Havana to renounce his citizenship surrounded by his family and U.S. attorney.
"Rene went in and filled out all the paperwork necessary to renounce his citizenship," said his attorney Phil Horowitz. "He will be able to stay in Cuba after a couple more processes, and after the State Department issues a certificate of loss of nationality, he will be able to stay in Cuba forever."
Gonzalez is the first of the Cuban Five to return the island. The other four men continue to serve lengthy sentences in U.S. federal prisons. Their case strained already shaky United States-Cuba relations.
The Cuban government said that their agents had simply kept tabs on violent Cuban-American exile groups.
But federal prosecutors argued the men also had tried to infiltrate U.S. military installations and had provided information that led to the 1996 downing of two planes from the group Brothers to the Rescue, which searched for boats stranded in the Florida Straits. Four men flying from Florida to Cuba were shot down and killed by Cuban air force jets.
In 2012 Cuban officials offered to negotiate the release of the Cuban Five for Alan Gross, the U.S. State Department contractor jailed in Cuba for transporting banned communications equipment to the island.
But U.S. officials rebuffed those overtures, saying Gross had not spied in Cuba.