Police in Brazil can question former president Luiz Inacio Lula da Silva as they probe the massive money-laundering scandal at state oil giant Petrobras, the nation's Supreme Court ruled.

Brazil's top court issued its ruling late Friday, after being petitioned last month by police to interrogate Lula, who governed the country from 2003 to 2010.

The high court, which handles all cases involving federal politicians, is mired deep in the fallout from the Petrobras kickback and political payoff scandal that cost the company more than $2 billion in 2014.

In last month's court filing, police said Lula "in his capacity as chief executive of the country... could have benefited from the scheme at Petrobras, obtaining benefits for himself, his Workers' Party (PT), or even his government."

Lula's name has been mentioned in the testimony of some defendants in exchange for a reduction of their sentencing, but they also said there was no proof of the ex-president's involvement.

Some of Brazil's most senior government officials and private sector executives, as well as a growing list of political figures, are among the dozens already tainted by the growing scandal.

A former top aide to Lula was charged last month, as has the former treasurer of the ruling Workers' Party.

Their arrests brought the investigation closer to Lula and his successor, President Dilma Rousseff, who was chairwoman of Petrobras during the main period of the corruption scheme but who has not been accused of involvement.

The former president, in a statement released by his institute, said after the ruling that he is ready to cooperate with the probe.