SAO PAULO - The president of Brazil's governing Workers' Party (PT), legislator Gleisi Hoffmann, on Thursday said over five decades of spying by the United States against President Luiz Inacio Lula da Silva was an "affront to national sovereignty".

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"Very serious revelations by journalist Fernando Morais about United States espionage in Brazil," Hoffmann posted on social media site X, saying Lula da Silva was closely monitored throughout his career as a union leader and political activist by numerous US government agencies, including the Central Intelligence Agency (CIA) and the National Security Agency (NSA).

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Morais is the author of "Lula", a biography about the founder of the PT and Brazil's three-time president.

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Leading newspaper Folha de Sao Paulo reported on Thursday that the US law firm Pogust Goodhead, which works pro bono for Morais in the United States, had access to US documents produced on Lula da Silva, including intelligence reports.