Former Argentine president Cristina Fernandez de Kirchner has been charged over corruption allegations as a federal judge also ordered the freezing of $US633 million ($880 million) of her assets.

Her government "steered public contracts to a businessman close to her family", the BBC reported the judge as finding. She has previously denied any wrongdoing. Argentine presidents are paid an annual salary of $US131,400.

Fernandez, who led Latin America's second-biggest economy from 2007 to 2015, has said the case is politically motivated and "accused current President Mauricio Macri of plotting against her", the report said. When Fernandez took office, she succeeded her husband, Nestor Kirchner who had led the country for four years.

The judge has seized $US633 million worth of assets from former Argentina President Cristina Fernandez. Francisco Munoz

Judge Julian Ercolini also approved corruption charges against two of the president's former aides, ex-Planning Minister Julio de Vido and former Public Works Secretary Jose Lopez, as well as businessman Lazaro Baez.

Fernandez has been accused of favouring Baez's construction company, Austral, in the concession of contracts for public projects, the report said. Austral won more than 50 contracts for public projects during her two terms in office, Clarin newspaper reported.