Brazil's president, Dilma Rousseff, has launched a blistering attack on US espionage at the UN general assembly, accusing the NSA of violating international law by its indiscriminate collection of personal information of Brazilian citizens and economic espionage targeted on the country's strategic industries.
Rousseff's angry speech was a direct challenge to President Barack Obama, who was waiting in the wings to deliver his own address to the UN general assembly, and represented the most serious diplomatic fallout to date from the revelations by former NSA contractor Edward Snowden.
Rousseff had already put off a planned visit to Washington in protest at US spying, after NSA documents leaked by Snowden revealed that the US electronic eavesdropping agency had monitored the Brazilian president's phone calls, as well as Brazilian embassies and spied on the state oil corporation, Petrobras.
"Personal data of citizens was intercepted indiscriminately. Corporate information – often of high economic and even strategic value – was at the centre of espionage activity.
"Also, Brazilian diplomatic missions, among them the permanent mission to the UN and the office of the president of the republic itself, had their communications intercepted," Rousseff said, in a global rallying cry against what she portrayed as the overweening power of the US security apparatus.
"Tampering in such a manner in the affairs of other countries is a breach of international law and is an affront of the principles that must guide the relations among them, especially among friendly nations. A sovereign nation can never establish itself to the detriment of another sovereign nation. The right to safety of citizens of one country can never be guaranteed by violating fundamental human rights of citizens of another country."
Washington's efforts to smooth over Brazilian outrage over NSA espionage have so far been rebuffed by Rousseff, who has proposed that Brazil build its own internet infrastructure.
"Friendly governments and societies that seek to build a true strategic partnership, as in our case, cannot allow recurring illegal actions to take place as if they were normal. They are unacceptable," she said.
"The arguments that the illegal interception of information and data aims at protecting nations against terrorism cannot be sustained. Brazil, Mr President, knows how to protect itself. We reject, fight and do not harbour terrorist groups," Rousseff said.
"As many other Latin Americans, I fought against authoritarianism and censorship and I cannot but defend, in an uncompromising fashion, the right to privacy of individuals and the sovereignty of my country," the Brazilian president said. She was imprisoned and tortured for her role in a guerilla movement opposed to Brazil's military dictatorship in the 1970s.
"In the absence of the right to privacy, there can be no true freedom of expression and opinion, and therefore no effective democracy. In the absence of the respect for sovereignty, there is no basis for the relationship among nations."
Rousseff called on the UN oversee a new global legal system to govern the internet. She said such multilateral mechanisms should guarantee the "freedom of expression, privacy of the individual and respect for human rights" and the "neutrality of the network, guided only by technical and ethical criteria, rendering it inadmissible to restrict it for political, commercial, religious or any other purposes.
"The time is ripe to create the conditions to prevent cyberspace from being used as a weapon of war, through espionage, sabotage and attacks against systems and infrastructure of other countries," the Brazilian president said.
As host to the UN headquarters, the US has been attacked from the general assembly many times in the past, but what made Rousseff's denunciation all the more painful diplomatically was the fact that it was delivered on behalf of large, increasingly powerful and historically friendly state.
Obama, who followed Rousseff to the UN podium, acknowledged international alarm at the scale of NSA snooping revealed by Snowden. He said: "Just as we reviewed how we deploy our extraordinary military capabilities in a way that lives up to our ideals, we have begun to review the way that we gather intelligence, so as to properly balance the legitimate security concerns of our citizens and allies, with the privacy concerns that all people share."
Brazilian officials said that Washington had told them about this review but had noted that its results would not be known for months and that Rousseff believed it was urgent to raise the need for an international code of ethics for electronic espionage.
Rousseff will leave New York tomorrow without meeting Obama but Brazil's new foreign minister, Luiz Alberto Figueiredo, will remain at the UN throughout the week and will meet his opposite number, John Kerry, Brazilian officials said, in an attempt to start mending the rift between the two countries.