Washington (CNN) The Trump administration on Monday slapped sanctions on a key ally of President Vladimir Putin who the Treasury Department said financed an internet troll factory that deployed social media campaigns in an attempt to influence the 2018 US midterm elections.

The Treasury Department for the first time used new executive authorities, meant to ward off foreign actors from interfering in US elections, to target Yevgeny Prigozhin , the Russian financier behind the Internet Research Agency. The firm was indicted by special counsel Robert Mueller for interfering in the 2016 elections.

The US government also took the additional step Monday of putting limits on Prigozhin's assets -- including the Russian's luxury personal property of three aircraft and a yacht used for his family's international vacations -- as well as on six employees of the agency he finances.

Anyone doing business with Prigozhin or using his planes or yachts now faces the prospect of US sanctions themselves.

2020 elections

The Treasury Department made clear that it was targeting Prigozhin and the Internet Research Agency for "its attempts to subvert American democratic processes" in 2018, but it also stressed that the US was watching other foes as the 2020 presidential vote approaches.

"Free and fair elections are the cornerstone of American democracy, and we will use our authorities against anyone seeking to undermine our processes and subversively influence voters," said Treasury Secretary Steven Mnuchin in a statement. "This Administration will work tirelessly to safeguard our electoral process, and will aggressively pursue any other foreign actor that attempts to interfere in the 2020 elections."

A statement by Treasury identified other actors the department is watching: "While today's action only targets Russian actors, the U.S. Government is safeguarding our democratic processes from adversaries -- primarily Russia, Iran, and China -- that may be seeking to influence the upcoming 2020 elections."

Treasury added that while it was sanctioning Prigozhin and others for their activities in the 2018 midterms, there "was no indication that foreign actors were able to compromise election infrastructure that would have prevented voting, changed vote counts, or disrupted the tallying of votes."

The move to sanction Russian efforts to undermine US democracy comes as President Donald Trump is under intense scrutiny for pressuring Ukraine to investigate former Vice President Joe Biden and his son in exchange for weapons systems it wanted to defend against Russia.

Lawmakers pursuing an impeachment inquiry against Trump have condemned his efforts -- obscured by White House officials who tried to hide records of the call in a classified system -- as an attempt to have a foreign country interfere in the 2020 elections. Analysts say the effort has served to strengthen Russia, which has occupied Crimea and continues to conduct a war in eastern Ukraine.

Treasury said Prigozhin spent significant funds to further the Internet Research Agency's attempted influence operations in connection with the 2018 midterm elections.

The organization used fictitious personas on social media and disseminated false information in an effort to influence the 2018 elections and try to undermine faith in US democratic institutions. Among other examples, Treasury cites a 2018 statement on the website "Internet Research Agency American Division" claiming that the organization sought to discredit candidates it deemed hostile to Russia and that it was utilizing social media to further its campaign.

Putin's 'personal chef'

Prigozhin had previously been indicted by the US in a case involving a troll factory that spearheaded Russian efforts to interfere in the 2016 elections. The Treasury Department also slapped the Internet Research Agency with sanctions in March 2018.

In addition to Prigozhin, Treasury announced it is imposing sanctions on six members of the Internet Research Agency for their work at the organization.

"As of 2018, Dzheykhun Nasimi Ogly Aslanov (Aslanov), Mikhail Leonidovich Burchik (Burchik), Vadim Vladimirovich Podkopaev (Podkopaev), Vladimir Dmitriyevich Venkov (Venkov), Igor Vladimirovich Nesterov (Nesterov), and Denis Igorevich Kuzmin (Kuzmin) were all members of the Internet Research Agency involved in attempting to interfere in U.S. elections," Treasury said in a press release.

Prigozhin has a colorful past.

Known as Putin's "personal chef," he spent nine years in prison in the 1980s for fraud and robbery, according to Russian media reports. After his release, he went into the catering business -- renovating a boat and opening New Island, one of a half-dozen upscale restaurants he owns in St. Petersburg. Putin turned to him to cater his birthday parties as well as dinners with visiting leaders.

In 2002, he served caviar and truffles to President George W. Bush during a summit in St. Petersburg.