Since the US president is unable to pardon state crimes, the collaboration could also be seen as an effort to pressure Manafort to cooperate in the broader Russia investigation under Mueller, Politico reported.
CNN has not independently confirmed the report.
The move, which Politico reported on Wednesday night, is another indication that Mueller is ramping up pressure on Manafort, who served as the former chairman of President Donald Trump's campaign. Manafort has not been accused of any wrongdoing, but he is seen as a central figure in Mueller's investigation into Russia's 2016 election meddling.
Messages to a Schneiderman spokesperson weren't immediately returned.
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