BUENOS AIRES

(Reuters) – South American leaders, outraged by the diversion of a Bolivian presidential plane in Europe over the Edward Snowden affair, weighed on Wednesday whether to hold an emergency summit to denounce what some called a U.S.-led act of aggression.

Bolivian President Evo Morales was en route from a conference in Moscow to his home on Tuesday when France and Portugal abruptly banned his plane from their airspace on suspicions it was carrying fugitive U.S. spy agency contractor Snowden, who is wanted by Washington.

The unusual treatment of the Bolivian leader touched a sensitive nerve in the region, which has a history of U.S.-backed coups, and other presidents rallied in support of Morales.

“Definitively, they’re all crazy,” Argentine President Cristina Fernandez wrote on her Twitter account after a phone call to Morales, who was stranded in Vienna overnight.

Fernandez described Morales as defiant. “‘I’m not a thief,'” she quoted him as saying, although he was unable to prevent Austrian officials from searching his aircraft. Snowden was not onboard.

Nicaragua and Cuban officials also decried the incident.

The 12-nation UNASUR group, which includes leftist leaders of Venezuela, Ecuador, Argentina and Bolivia as well as the more moderate Chile and Brazil, issued a statement, calling France’s and Portugal’s actions “dangerous.”

UNASUR’s secretary general said the group was coordinating with member nations to set a date and place for an emergency summit.

Snowden is believed to be still in the transit area of a Moscow airport, where he has been trying since June 23 to find a country that will offer him refuge from prosecution in the United States on espionage charges.

U.S. President Barack Obama has warned that giving

Snowden asylum would carry serious costs.

Bolivian Vice President Alvaro Garcia told reporters that Morales had been “kidnapped by the empire.” Defense Minister Ruben Saavedra accused the United States of strong-arming the Europeans into withdrawing the flight permits, although the restrictions were lifted and Morales is now on his way home.

Bolivia has filed a formal complaint with the United Nations and has called in diplomats from the French, Italian and Portuguese embassies in La Paz to demand an explanation.

In Ecuador, President Rafael Correa called the Europeans’ actions “extremely grave.”

“We’re trying to convene a meeting of … presidents, and take measures against this affront to Latin America,” he wrote on Twitter. “How they’ve trampled upon international law!”

(Reporting by Daniel Ramos in La Paz, Marco Aquino in Lima, Louise Egan in Buenos Aires; Writing by Louise Egan; Editing by Eric Beech)