Obama moves to defuse spying row with Brazil, Mexico

President Barack Obama moved to defuse a row with Brazil and Mexico over alleged US spying on leaders of the Latin American countries, promising them that the United States would cooperate with them to "address concerns" over the claims.

His pledge appeared to have had some effect towards easing tensions with the Latin American giants, as Brazilian President Dilma Rousseff was not only all smiles as Obama took his place next to her during a group photograph session Friday at the G20 summit, but she also reciprocated when he leaned over to kiss her on the cheek.

Outrage followed the Sunday report by US journalist Glenn Greenwald, who has access to documents leaked by fugitive former NSA contractor Edward Snowden, that the National Security Agency snooped on communications of Rousseff and Mexico's Enrique Pena Nieto.

On Thursday, Brazil halted preparations for Rousseff's October visit to the United States -- which would have been her first to Washington and the first state visit by a foreign leader this year.

Mexico meanwhile demanded an investigation into the claims.

With all three leaders in Saint Petersburg for the G20 summit, Obama went to damage control mode, and held separate bilateral talks with Rousseff and his Mexican counterpart Pena Nieto on Thursday.

"With President Pena Nieto as with President Rousseff, President Obama underscored that we'll continue to work with the governments of Brazil and Mexico to address concerns that they have about the disclosures that have been made regarding the NSA," said Ben Rhodes, Obama's deputy national security advisor for strategic communications.

"This is an ongoing process that we will work through with the Brazilian and Mexican governments," he said.

Greenwald, who is based in Rio de Janeiro, reported Sunday that the NSA was using a programme to access all Internet content Rousseff visited online.

He told Globo television that the NSA was trying to better understand Rousseff's methods of communication and interlocutors.

The NSA programme allegedly allowed agents to access the entire communications network of the president and her staff, including telephone, Internet and social network exchanges, the Rio-based journalist said.

He also said some of Pena Nieto's email, phone calls and text messages were intercepted, including communications in which he discussed potential cabinet members before he was elected in July 2012.

On Monday, both Brazil and Mexico summoned the US ambassadors in their respective countries to demand an explanation for the latest disclosures.

Brazilian Foreign Minister Luis Figueiredo said that, if proven, the report that Rousseff was spied on "represents an unacceptable and impermissible violation of Brazilian sovereignty".

Communications Minister Paulo Bernardo said the scope of the espionage was broader and more serious than initially thought.

"All of the explanations given (by the United States) since the start of these episodes are revealed to be false," he said Tuesday.