(Credit: Shannon Stapleton/Reuters)

Brazilian President Dilma Rousseff is incensed by the U.S.'s NSA surveillance programs, and today she let her anger boil over on the world stage.

In a scathing speech at the U.N., delivered moments before President Obama took to the podium, Rousseff accused the U.S. of violating international law and the fundamental values of democracy.

"What we have before us, Mr. President, is a serious case of violation of human rights and civil liberties; a case of invasion and capture of confidential secret information pertaining to business activities; and above all, a case of disrespect to national sovereignty, the national sovereignty of my country," she told the General Assembly.

"We have let the U.S. government know about our protest by demanding explanations, apologies and guarantees that such acts or procedures will never be repeated again," she added.

The White House has resisted making any public apology or even acknowledgement of the surveillance activity itself. Officials have only said that they "regret" the concerns raised by Brazil in the wake of unauthorized disclosures of NSA activities by Edward Snowden.

Despite aggressive, personal outreach from Obama and top U.S. diplomats to explain American intelligence operations, Rousseff has remained defiant. One week ago she cancelled a state visit to the U.S. planned for October, citing displeasure over spying.

"Meddling in such a manner in the affairs of other countries is a breach of international law and as such it is an affront to the principles that should otherwise govern relations among countries, especially among friendly nations," she said today.

"The argument that illegal interception of information and data is allegedly intended to protect nations against terrorism is untenable," she said, alluding to U.S. claims.

"Without the right to privacy, there is no real freedom of speech or freedom of opinion and, therefore, there is no actual democracy," she said. "Without respect to sovereignty, there is no base for proper relations among nations."

National security council spokeswoman Caitlin Hayden said Obama and Rousseff recently agreed to work together to "move beyond this issue as a source of tension in our bilateral relationship."

"We have made clear that the United States gathers foreign intelligence of the type gathered by all nations," she said. "As the president said in his speech today at the U.N. General Assembly, we've begun to review the way that we gather intelligence, so that we properly balance the legitimate security concerns of our citizens and allies with the privacy concerns that all people share."