Donald Trump
Donald Trump Reuters

U.S. President Donald Trump’s former campaign manager, Paul Manafort, on Monday afternoon pleaded not guilty to charges from special counsel Robert Mueller, who is conducting an investigation into ties between the Trump campaign and Russia.

Manafort's former business associate, Richard Gates, also pleaded not guilty, according to The Hill.

Manafort surrendered himself to FBI agents on Monday morning after being charged with 12 counts, including conspiracy against the U.S. The indictment also included Gates.

The 31-page indictment, unsealed on Monday morning, lays out the charges, which are related to work Manafort and Gates did on behalf of a Kremlin-backed political party in Ukraine. Mueller alleges the two men were paid tens of millions of dollars that they then laundered “in order to hide Ukraine payments from United States authorities.”

Manafort is accused in the indictment of using the laundered money to buy luxury goods in the U.S.

The indictment, however, makes no mention of Manafort’s work for Trump’s campaign, which began in March of 2016 and ended with his ouster in August.

Speculation has roiled that Mueller may be attempting to push Manafort to cooperate with the broader Russia probe.

Mueller was appointed in May by the Justice Department as special counsel to oversee the federal investigation into alleged Russian interference in the 2016 election.

His appointment was announced after Attorney General Jeff Sessions previously recused himself from any involvement in the Russia investigation due to his role as a prominent campaign adviser and surrogate.

Trump has argued that Mueller has hired "Hillary Clinton supporters" and people who worked for Clinton's 2016 White House bid to work on his investigation.

Indeed, reports emerged last week that a controversial dossier against Trump compiled ahead of the 2016 presidential election, which suggested then-candidate Trump colluded with the Russian government, was produced at the behest of the Clinton campaign and the Democratic National Committee.