Uruguay has inaugurated its first left-wing president, Tabare Vazquez, in front of several of Latin America's most prominent leftist leaders.
Tabare Vazquez is Uruguay's first left-wing president
Thousands of Uruguayan supporters celebrated in the streets of the capital, Montevideo, as he took office.
President Vazquez restored full diplomatic relations with Cuba immediately after being sworn in.
He said that ties between the two countries - severed in 2002 - should never have been broken off.
Mr Vazquez, whose win in presidential elections in October ended almost 180 years of two-party rule, promised to "work tirelessly" for Uruguay's people.
Uruguay becomes the fifth Latin American nation to move to the left.
Mr Vazquez was sworn in for a five-year term in front of leaders including Brazil's Luiz Ignacio Lula da Silva, Venezuela's Hugo Chavez and Argentina's Nestor Kirchner.
Cuba's President Fidel Castro cancelled his trip at the last minute, citing health reasons, but Foreign Minister Felipe Perez Roque did attend the ceremony.
Uruguay broke off diplomatic ties with Cuba three years ago under outgoing President, Jorge Battle, after Fidel Castro accused him of being a traitor for supporting US efforts to condemn Cuba's human rights record in a United Nations vote.
The Cuban minister and his Uruguayan counterpart Reinaldo Gargano signed the agreement restoring relations.
"It is with great pleasure that I am welcoming the Cuban people once again at this house and thus strengthening that friendship and ties that should never have been broken," said President Vazquez.
Focus on poverty
The 65-year-old's win at the head of the Frente Amplio (Broad Front) coalition party ended the long dominance of the ruling Colorado Party, beaten into third place, and the National Party, whose candidate came second.
"I swear to work tirelessly for the prosperity of the Uruguayan people," Mr Vazquez said as he took office, also promising to respect the constitution.
The BBC's Elliott Gotkine in Uruguay says the country's shift to the left is down to disillusionment with the right and the failure of its economic policies.
The left has also rejected many policies which had scared off voters in the past, he says.
Most analysts expect Mr Vazquez to emulate Brazil's President Lula by maintaining a broadly unchanged economic policy but placing greater emphasis on poverty and jobs, our correspondent adds.
Mr Vazquez, a former mayor of Montevideo, signed a $100m anti-poverty programme as one of his first acts in office.
"We have pledged changes and we will bring in changes," he said.