Venezuelan President Hugo Chavez is hosting a summit of a new regional bloc that brings together 33 nations of Latin America and the Caribbean. The general aim of the group, which does not include the US or Canada, is to foster regional ties. Mr Chavez has described the bloc as a counter to US influence in the region.
The two-day summit is Mr Chavez's first big international event since he was treated for cancer and forced to postpone the original meeting in July. The summit in the Venezuelan capital, Caracas, will be the inaugural gathering of the Community of Latin American and Caribbean States, known by its Spanish initials, Celac.
It will be a further addition to regional groupings that include the Organisation of American States (OAS), Unasur, Mercosur, Alba and the Caribbean Community (Caricom). Unlike the long-established OAS, Celac does not include the US or Canada. And unlike the OAS, it will include Cuba, which in 2009 rejected an invitation to rejoin the Washington-based body after a long exclusion.
Mr Chavez has described the summit, with some rhetorical flourish, as "the most important political event to have happened in our America in 100 years".
For the Venezuelan president, Celac forms part of his dream of realising Latin American unity and also creating a counterweight to Washington but for other regional leaders, the aims are less grand though no less important, correspondents say.
These include examining the region's response to the global financial crisis, promoting economic development and discussing joint efforts to tackle drug-trafficking. And Celac's birth does not herald the demise of the OAS, analysts say.
"[The OAS] has clearly defined purposes and principles to guide it. Its procedures are in place. And it has a budget - most of which comes from the US and Canada," Peter Hakim, president emeritus of the Inter-American Dialogue think tank, told the AFP news agency.
The inaugural summit was due six months ago but was postponed because Mr Chavez was recovering from surgery to remove a cancerous growth. The talks on Friday and Saturday will be watched for indications of Mr Chavez's current health. The Venezuelan president has said he is completely recovered after four rounds of chemotherapy.
He is expected to run in next October's presidential election for another six-year term.
Analysis by Sarah Grainger BBC News, Caracas:
The US and Canada were deliberately excluded from this summit, but Cuban President Raul Castro has been welcomed with open arms.
The heads of state of 32 countries in the region have come to Caracas for the inauguration of the new organisation. Only President Humala has stayed away, amid continuing protests over mining in Peru.
While US exclusion from the meeting is clearly a snub to Washington, the Venezuelan government says the new organisation will foster regional ties and look at ways of insulating the region from economic problems in the US and Europe.