The Venezuelan Foreign Ministry stated that the Brazilian message contains "comments full of deep ignorance and misinformation about the political reality in Venezuela."
Last year, the Venezuelan government once again claimed the territory, and Venezuelan voters approved its incorporation in a referendum held in December.
At the Mercosur meeting, Minister Vieira underscored the significance of persistently fortifying the regional bloc to foster the development of the entire continent.
The move comes as Venezuelans prepare to vote in a referendum regarding Venezuela's claims over the Essequibo region, constituting about two-thirds of Guyana.
The presidents of Chile, Gabriel Boric, and Uruguay, Luis Lacalle Pou, reacted to Lula's statements after his meeting with Venezuelan president Nicolás Maduro the day before the summit.