CARACAS, Venezuela (AP) — A group of former presidents has held secret meetings in the Dominican Republic with Venezuelan officials and government opponents in an attempt to mediate the deeply polarized South American nation's political standoff, an opposition leader confirmed Saturday.

Jesus Torrealba, executive secretary of the opposition alliance, said that the meetings took place under the auspices of the Union of South American Nations. But he said there was no face-to-face encounter, and instead the two sides exchanged messages through the ex-presidents.

Telesur reported that the Venezuelan government was represented in the Friday meetings by Foreign Minister Delcy Rodriguez and two top officials in the ruling socialist party. Three lawmakers were there for the opposition.

Venezuela's opposition is pushing for a referendum on whether to recall President Nicolas Maduro amid a severe economic crisis marked by triple-digit inflation and shortages of basic goods.

The meetings came a week after ex-presidents Jose Luis Rodriguez Zapatero of Spain and Leonel Fernandez of the Dominican Republic announced they would seek to initiate a "national dialogue" in Venezuela. Panamanian former President Martin Torrijos was also part of the international commission.

Following criticism that the encounters were held in secret, Torrealba said via Twitter that opposition representatives stressed several "indispensable" demands for any dialogue: allowing the recall referendum to proceed, the release of people it considers political prisoners, solving the economic crisis and for the government to "respect" the constitution and the opposition-controlled congress.

He added that the opposition would provide details on the content of the Dominican meetings when its representatives return to Venezuela.