Luiz Inacio Lula da Silva

The ruling came on a request filed by investigators Sept. 11 who said they wanted to question Silva about possible involvement in the scheme. Under Brazilian law, all federal politicians and some at other levels can be investigated only if the Supreme Court approves the inquiry.

A press officer at the Federal Prosecutors Office said Thursday that enough evidence has been gathered to warrant a full-fledged investigation into Silva's alleged overseas lobbying efforts in favor of Brazil's biggest builder. Citing internal regulations the press officer spoke on condition of anonymity.