Brazil's top prosecutor on Tuesday asked the Supreme Court to open a probe into alleged obstruction of justice by President Dilma Rousseff, major Brazilian newspapers reported in a potentially explosive twist to the country's political crisis.

According to reports in Globo, Folha de Sao Paulo and Estadao dailies, chief prosecutor Rodrigo Janot has requested authority to open an investigation into the embattled president and also her predecessor and key political ally Luiz Inacio Lula da Silva.