Guardian whistle-blower Edward Snowden has offered to help the Brazilian government investigate claims of US spying on their citizens if the South American country offers him political asylum.
Ex- National Security Agency worker Snowden is currently in Russia.
According to a report by the Associated Press, Snowden has written an open letter to a Brazilian newspaper offering his assistance.
Brazilian politicians areinterested in talking to Snowden after he revealed the widespread hacking of transatlantic fibre-optic cables leaving the South American country by the NSA.
He said in the letter: "I've expressed my willingness to assist where it's appropriate and legal but, unfortunately, the US government has been working hard to limit my ability to do so.
"Until a country grants me permanent political asylum, the US government will continue to interfere with my ability to speak out."
Snowden’s main media contact Glenn Greenwald lives in Brazil.
Meanwhile, a US district judge has ruled that the bulk collection of American telephone records by the NSA is probably unconstitutional as it contravenes rules outlawing unreasonable searches.