Bolivian President Evo Morales arrived here on Sunday to meet with his Ecuadorian and Venezuelan counterparts, Rafael Correa and Hugo Chavez.
The three presidents will discuss issues on the Union of South American Nations (Unasur) at a private lunch.
Ahead of their meeting, the three presidents took part in ceremonies marking the Battle of Pichincha of May 24, 1822, in which Ecuador won its independence from Spain.
They also visited the National Temple and the tomb of the independence hero Antonio Jose de Sucre.
Ecuador and Venezuela signed agreements on Sunday to cooperate in energy, mining, tourism, agriculture and finance.