ST. PETERSBURG, Russia — Brazilian President Dilma Rousseff, angered by a recent report that the U.S. government spied on her communications, said on Friday that President Barack Obama had taken responsibility for what happened and that she may still proceed with a planned visit to Washington next month.

Rousseff, speaking to reporters following a one-on-one meeting with Obama on the sidelines of the G-20 summit in Russia late on Thursday, said the U.S. president had agreed to respond formally to the spying allegations by next Wednesday.

"My trip to Washington depends on the political conditions to be created by President Obama," said Rousseff, according to the official Twitter feed of Brazil's presidency.

White House official told Reuters that Obama and Rousseff had discussed the alleged eavesdropping by the National Security Agency (NSA), which may have also targeted the communications of Mexican President Enrique Pena Nieto, but the official did not provide any details.

Obama and Rousseff sat next to one another at the first plenary session of G-20 leaders.

Rousseff, furious over the alleged monitoring of her emails and phone calls by the NSA, this week called off a trip by an advance team to Washington to prepare for a state visit to the United States by the Brazilian leader.

Pena Nieto, who was also attending the G-20 summit, said he had spoken to Obama about the matter and Obama had assured him he would launch a "full investigation" into allegations that the NSA had spied on Pena Nieto's communications last year.

"He clearly informed me that he is also interested in clearing up this issue so it does not become a topic that could eventually tarnish the relationship we are building," Pena Nieto said in an interview with Mexican broadcaster Televisa.

Brazil's presidential palace said the canceled trip to Washington was for a team of logistical planners, security personnel and protocol officers that would have left this weekend to start preparing the Oct. 23 visit.

Rousseff's visit, which is the only such invitation extended by Obama this year, is intended to highlight a recent improvement in relations between the two biggest economies in the Americas, as well as Brazil's emergence over the past decade as a vibrant economy and regional power.

The Brazilian government had given the United States until Friday to give it a written explanation of what the NSA was doing monitoring Rousseff's communications, as reported on Sunday by a Brazilian television program based on documents leaked by former NSA contractor Edward Snowden.

Ben Rhodes, a deputy U.S. national security adviser, said Washington will work to resolve the dispute through "diplomatic and intelligence channels."

"We understand how important this is to the Brazilians. We understand their strength of feeling on the issue," he said. "What we're focused on is making sure the Brazilians understand exactly what the nature of our intelligence effort is."