The U.S. government’s decision to restore diplomatic relations with Cuba after more than 50 years is key to Washington’s understanding the new era in Latin American, Venezuelan President Nicolas Maduro wrote in a letter published Friday in Cuban official media.

Maduro sent letters to Cuban President Raul Castro and the head of state’s predecessor and older brother, Fidel Castro, following the Dec. 17 announcement of a renewal of ties between Washington and Havana.

“There is a still a long way to go for Washington to recognize that we are no longer their backyard, to end the criminal blockade against the Homeland of (Jose) Marti and Fidel,” the Venezuelan said in his message to Raul Castro.

“However, I think this is a very important step for the United States to understand that here, in our land, there is a change of era, that the Greater Homeland changed forever and that it will not regress,” Maduro wrote.

In his missive to Fidel Castro, Maduro hailed the significance of the U.S. decision to release three Cuban spies in exchange for an American intelligence operative held in Havana and Cuba’s “humanitarian” release of U.S. government subcontractor Alan Gross.