A meeting the presidents of Brazil, Bolivia, Ecuador, and Venezuela, Luiz Inácio Lula da Silva, Evo Morales, Rafael Correa, and Hugo Chávez, respectively, were scheduled to hold late this month was suspended because of "agenda issues," official sources said on Monday.

"It has been impossible to combine the agendas of the presidents and the meeting was put off," a spokesman for the Brazilian presidential palace of Planalto told Efe.

Chávez announced the reunion during the summit of the Union of South American Nations (Unasur) in Brasilia last month. The meeting was supposed to take place in Manaus, Brazil, late this month, following President Lula's visit to Venezuela.

Lula is arriving in Venezuela next Thursday to meet with Chávez.

Next week the four presidents are to meet during a summit of the Common Market of the South (Mercosur) in Tucuman, northeast Argentina.