Venezuela's President-elect Nicolas Maduro gestures as he holds the certificate given him by the National Electoral Council (CNE), confirming him as winner of Sunday's election, in Caracas, April 15, 2013. REUTERS

South American governments have moved quickly to back Venezuelan President-elect Nicolas Maduro, whose slim victory on Sunday is being disputed by the political opposition amid calls for a recount.

The Union of South American Nations, or Unasur, has released a statement expressing support for the results of the Venezuelan presidential election in which Socialist party candidate Maduro narrowly defeated opposition challenger Henrique Capriles Radonski with 51 percent of the vote.

“The Unasur electoral commission congratulates the Venezuelan people for the civic and democratic spirit demonstrated on the occasion of the election of April 14,” read the statement.

Capriles has refused to accept the electoral results without a recount, while the 12-member organization -- which includes the governments of Argentina, Bolivia, Brazil, Chile, Colombia, Ecuador, Guyana, Peru, Paraguay, Suriname, Uruguay and Venezuela -- urged all parties to respect the outcome.

“These results must be respected,” Unasur said. “Any claim, question or extraordinary procedure applying to any of the participants of the electoral process must be channeled and resolved within the existing legal framework.”

South American leaders, including the presidents of Argentina and Brazil, have congratulated Maduro on his victory, demonstrating firm support from the region’s two largest economies.

“Congratulations to President Nicolas Maduro. My eternal gratitude to my dear friend and partner Hugo Chavez,” wrote Argentine President Cristina Fernandez de Kirchner in a Twitter post, paying tribute to the Maduro’s predecessor and recently deceased leader of the socialist movement in Venezuela.

Brazilian President Dilma Rousseff personally called Maduro to extend her support, saying she was prepared to work with the new government of the oil-rich OPEC nation, according to an entry on the presidential blog.

Despite Unasur’s approval of the results, Colombia -- South America’s third-largest economy -- has yet to recognize Maduro’s victory.

The Organization of American States -- composed of 35 member states throughout North and South America, including the United States -- has also not recognized the results and supported the Venezuelan opposition’s call for recount.

“In a context of deep division and political polarization, as shown by the electoral process, the leader of the OAS made ​​a fervent call for a national dialogue to help calm the mood of the Venezuelan society and to help chart a common path to strengthen the governability of the country,” read an OAS statement.