President Obama had a quick chat and shook hands with Cuban President Raul Castro at the memorial service for former South African President Nelson Mandela.
It appeared to be a friendly exchange.
The United States has not had diplomatic relations with Cuba since the communist revolution led by Castro's brother Fidel more than 50 years ago.
Jim Waterson is a politics editor for BuzzFeed News and is based in London.
Contact Jim Waterson at email@example.com.
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