The Mexican government summoned the US ambassador and demanded an investigation on Monday into allegations that the National Security Agency spied on President Enrique Pena Nieto.
The foreign ministry said in a statement that a diplomatic note was sent to Washington requesting "an
exhaustive investigation" to determine who may be responsible for the alleged spying on Pena Nieto's emails before his election last year.
The government said it would not "prejudge" the veracity of the allegations reported by US journalist Glenn Greenwald but that it "categorically rejects and condemns any spying work on Mexican citizens in violation of international rights."
Greenwald, who obtained secret files from NSA leaker Edward Snowden, told Brazil's Globo television on Sunday that the agency tracked Brazilian President Dilma Rousseff's use of the Internet and accessed emails of Pena Nieto.