Government leaders in Mexico and Brazil—among the closest US allies in Latin America—expressed outrage at Sunday's revelations that the US has been secretly spying on the presidents of both countries, summoning their US ambassadors on Monday to demand a formal explanation.

Brazil's Foreign Minister Luiz Alberto Figueiredo declared that, if the reports are confirmed, they would constitute "an inadmissible and unacceptable violation of Brazilian sovereignty."

A statement from Mexico's foreign ministry reads, "Without prejudging the veracity of the information presented in the media, the Mexican government rejects and categorically condemns any espionage work against Mexican citizens in violation of international law."

"If true, it seriously violates national sovereignty," Rep. Fernando Zarate, secretary of the Mexican House of Representatives' Foreign Relations Committee and member of the Democratic Revolution Party, told CNN. "How is it possible that the telephone of a president is being monitored? What could an ordinary citizen in our country expect?"

Journalist Glenn Greenwald exposed the spying on a Sunday evening show of Brazilian news program Fantastico, citing documents provided by NSA whistleblower Edward Snowden which  revealed NSA programs that monitor email and phone communications of President Mexican President Enrique Pena Nieto and Brazilian President Dilma Rousseff.

This diplomatic row is the latest development in a spying scandal, exposed by Snowden, that has ricocheted across the world. It follows on the heels of revelations that Mexico and Brazil are heavily targeted by NSA spying programs that go after government and trade secrets.

_____________________