Brazil says it is working with other countries to draft a United Nations General Assembly resolution that would guarantee people's privacy in electronic communications.
The move follows a series of reports of alleged US eavesdropping on foreign leaders and others that has surprised and angered allies.
Brazil's President Dilma Rousseff has been especially outspoken and took the rare step of cancelling a state visit to Washington after secret documents leaked by former National Security Agency analyst Edward Snowden showed that the NSA hacked the computer network of Brazil's state-run oil company Petrobras and scooped up data on emails and telephone calls flowing through the country.
Latin American and European diplomats said Brazil and Germany were leading efforts on the draft resolution. German chancellor Angela Merkel and other European leaders expressed anger this week after reports that the NSA allegedly monitored Mrs Merkel's mobile phone and swept up millions of French telephone records.
The general assembly resolution would be non-binding, but it would be seen as another expression of disapproval of the alleged US spying.
Brazil's Foreign Ministry confirmed that the country was drafting a UN resolution.
"What I can tell you is that the Brazilian Mission in the United Nations has drawn up a proposal calling for the right to privacy on the internet," said a ministry press officer.
Washington has contended that it is necessary to intercept vast amounts of electronic data to effectively fight terrorism, but the White House has said it is examining countries' concerns as part of an ongoing review of how the US gathers intelligence.
A diplomat with a major European nation expected easy passage in the general assembly because the resolution would not have language that would be "offensive" to any nation, particularly the United States.
The diplomat said the resolution would expand the right to privacy guaranteed by the International Covenant on Civil and Political Rights, which went into force in 1976.
The draft would be forwarded within the week to the general assembly sub-committee that deals with social, humanitarian, cultural and human rights issues, and then to the full assembly for consideration in late November.