President Barack Obama's national security adviser has conceded there are legitimate questions about US spying on its allies, as America sought to soothe Brazil's concerns about far-reaching surveillance by the National Security Agency.
A White House meeting between Susan Rice and Brazil's foreign minister, Luiz Alberto Figueiredo, constituted the latest attempt by the Obama administration to stem the damage to foreign relations inflicted by revelations by NSA leaker Edward Snowden. But it was not immediately clear whether that damage had been repaired.
In the meeting, Ms Rice acknowledged that recently-revealed surveillance programmes sparked tensions in an otherwise close US-Brazilian relationship, said Caitlin Hayden, a spokeswoman for the White House's National Security Council.
She said some of the NSA's activities had been distorted by Mr Snowden's leaks to the news media while others "raise legitimate questions for our friends and allies about how these capabilities are employed". "The United States is committed to working with Brazil to address these concerns, while we continue to work together on a shared agenda of bilateral, regional and global initiatives," Ms Hayden said.
Brazilian president Dilma Rousseff has been among the most vocal of foreign leaders expressing outrage over US spying. After leaked documents showed US spy agencies had monitored her communications, Ms Rousseff threatened to cancel a planned state visit to Washington.
After discussing the issue with Mr Obama during an economic summit last week in St Petersburg, Russia, Ms Rousseff asserted that spying on a friendly country was incompatible with democratic alliances. She said Mr Obama had promised answers and told her he did not want her to cancel her trip. "I want to know everything that they have. Everything," Ms Rousseff said.
The White House did not say what specifics, if any, Ms Rice offered Brazil, but even as the two officials prepared to meet in Washington, new revelations offered further fodder for Brazilian concerns about the surveillance.
A report on Sunday by Globo TV, based on leaked documents from Mr Snowden, said the NSA targeted Brazil's state-run oil company Petrobras. It also said the NSA targeted the Belgium-based Society for Worldwide Interbank Financial Telecommunication, an organisation that oversees international bank transfers thought to be secure transactions.
The NSA programmes have sparked international consternation from Latin America to Asia and Europe.
Mexican president Enrique Pena Nieto, who shared his concerns during his own private meeting with Mr Obama last week, has said reports the NSA had kept tabs on his communications, if true, would constitute an illegal act. And Mr Obama found himself on the defensive last week during a stop in Stockholm, Sweden, where he insisted the US was not targeting the personal communications of average Europeans but acknowledged that the programmes had not always worked as intended and said "we had to tighten them up".