US embassy officially reopens in Havana, Cuba

The U.S. flag is flying over the American embassy in Havana, Cuba, once again.

Friday's flag raising ceremony—the first time the stars and stripes has flown at the building in 54 years—marked a major milestone for the thawing relationship between the former Cold War enemies. John Kerry landed in Cuba earlier Friday, making him the first U.S. secretary of state to visit the country since 1945.

Recalling the history between the two nations—including the Bay of Pigs Invasion and the Cuban Missile Crisis—Kerry charted a new path forward.

"It doesn't take a GPS to realize the road of mutual isolation and estrangement that the United States and Cuba were travelling was not the right one, and that the time has come for us to move in a more promising direction," Kerry said.

But soon after Kerry heads home Friday evening, the Cuban and U.S. diplomats who negotiated the embassy reopening will launch full-time into the next phase of detente: expanding economic ties between the two nations with measures like direct flights and mail service.

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Washington is also seeking to resolve billions of dollars in half-century-old American claims over property confiscated after the Cuban revolution. For now, a U.S. embargo still exists on Cuba, but the White House favors Congress lifting those restrictions, Kerry emphasized Friday.

Looking to end decades of hostilities, Cuban President Raul Castro and President Barack Obama announced last December they would restore diplomatic ties and work to normalize relations.

Kerry described the diplomatic shift as a "courageous decision" on the part of Obama and Castro.

—The Associated Press and Reuters contributed to this report.