Luiz Inacio Lula da Silva has been serving eight years and 10 months for corruption

A Brazilian court Wednesday handed a near 13-year sentence to Luiz Inacio Lula da Silva, in a new corruption conviction for the former leftist president already serving a lengthy jail term in a separate case.

Lula, 73, was found guilty by a court in the southern city of Curitiba of accepting renovation work by two construction companies on a farmhouse in exchange for ensuring they won contracts with the state-run oil company Petrobras.

He was given a sentence of 12 years and 11 months by the court located in the southern city of Curitiba.

A legal expert, Thiago Bottino do Amaral of the Getulio Vargas Foundation, told AFP that, under Brazilian law, prison terms can be served one after the other as long as the total time behind bars does not exceed 30 years.

Lula, since April last year, is already serving a 12-year term for corruption in a separate case.

The leftist former leader ruled Brazil between 2003 and 2010.

He has denied all the charges against him, claiming they are politically motivated with the aim of preventing him competing in elections last year that were won by Brazil's new far-right President Jair Bolsonaro.

Defending himself in the latest case, he said the farmhouse did not belong to him and its title was in the name of one of his friends, Fernando Bittar.

But the Curitiba judge, Gabriela Hardt, was not persuaded, noting that "the family of ex-president Lula very often frequented the farm as if he was the owner." She also observed that Bittar had said in 2014 that his own family did not visit the property as often and that it was used more by Lula's family.

"The accused received these unjustified benefits because of his position as president of the republic, of whom exemplary behavior is demanded," she said.