The former president of Brazil, Luiz Inacio Lula da Silva, is to face charges connected with a money laundering investigation in a case that could deepen political crisis in the South American country.

State prosecutors have not yet specified the charges but newspaper O Globo reported they are for money laundering and hiding assets, such as a luxury apartment in the city of Guaruja.

The apartment officially belongs to the firm OAS, which is under investigation over claims it paid bribes to politicians and senior officials at the state-owned oil company Petrobras.

Lula, who was president between 2003 and 2011 says the accusations are politically motivated to stop him from running for president in 2018. Police had detained Lula on 4 March for questioning in a separate probe for graft which led to supporters gathering outside his home.

The charges Lula faces increases pressure on his successor Dilma Rousseff who herself is fighting impeachment regarding Petrobras and graft accusations that have inspired millions of people across Brazil to take to the streets.

Rousseff needs Lula's support to get the backing of the left-wing Workers' Party or PT and these charges he faces could put that in jeopardy.

The minister in charge of legislative affairs, Ricardo Berzoini, told Reuters that if Lula took a post in government he could get some protection from prosecution as it would mean he would be judged in the supreme court, rather than by a federal judge who is investigating the Petrobras kickbacks.

Political tensions are set to increase in Brazil in the coming weeks with both supporters and opponents of Lula planning street protests.

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