Paul Manafort, President Trump’s​ former campaign manager, and his former business partner surrendered to federal authorities Monday ​and face a 12-count indictment as part of special counsel Robert Mueller’s probe into Russian meddling in the 2016 election.

Manafort and Rick Gates were charged with conspiracy against the United States, conspiracy to launder money, unregistered agent of a foreign principal, false and misleading FARA statements, and seven counts of failure to file reports of foreign bank and official records, according to the federal ​indictment, referring to the Foreign Agent Registration Act.

They were indicted by a federal grand jury Friday, and the charges were unsealed after they turned themselves in Monday morning.

Manafort was hired to run Trump’s campaign in May 2016, but he was forced out just three months later when news reports began questioning his work for Ukrainian President Viktor Yanukovych, who has close ties to Russian President Vladimir Putin.

The indictment says Manafort and Gates worked as “unregistered agents” for Ukraine and the Party of Regions, a political party run by Yanukovych.

​They “generated tens of millions of dollars in income as a result of their Ukraine work” and hid the payments from US authorities, the indictment says.

From 2006 through 2016, Manafort and Gates laundered $75 million through “scores of United States and foreign corporations, partnerships and bank accounts,” it says.

The 31-page indictment does not mention Trump or the 2016 election.

The feds say Manafort laundered more than $18 million and “used his hidden overseas wealth to enjoy a lavish lifestyle in the United States, without paying taxes on that income”:

Manafort specifically purchased three residences in 2012 — a $2.8 million condominium on Howard Street in Soho, which he rented out on Airbnb, a $3 million brownstone on Union Street in Carroll Gardens, Brooklyn, and a home in Virginia.

Gates is accused of transferring $3 million from offshore accounts to others he controlled.

Gates, described as Manafort’s “right-hand man” in court papers, used the illicit funds to pay for personal expenses, including his mortgage, children’s tuition and interior decorating of his Virginia home.

Manafort and Gates allegedly “engaged in a multimillion-dollar lobbying campaign in the United States at the direction of Yanukovych” by secretly paying two unidentified firms in Washington, DC, $2 million from offshore accounts to do work for the Ukrainian government.