Special Counsel Robert Mueller has expanded his investigation to include business transactions involving President Trump’s companies and those of his associates, Bloomberg News is reporting.

The news comes a day after Trump appeared to caution Mueller against expanding his investigation in that direction.

“I think that’s a violation. Look, this is about Russia,” Trump said in an interview with The New York Times when asked whether Mueller will have crossed a red line by broadening the investigation to include Trump’s companies. (RELATED: Trump Delivers A Warning To Mueller)

Mueller was appointed special counsel in May to look into potential collusion between the Trump campaign and the Russian government, an allegation that Trump strongly denied.

According to Bloomberg, investigators are now looking into various real estate transactions involving Trump’s companies and wealthy Russians. Trump’s sale of a Florida mansion to a Russian oligarch in 2008 is of interest to investigators, according to Bloomberg. So is a SoHo real estate development deal between Trump Organization and Bayrock Capital, a real estate firm managed by Felix Sater, a Russian-American developer convicted of securities fraud in the 1990s.

Mueller is also reportedly looking at Trump’s dealings with Russian oligarch Aras Agalarov. Agalarov paid Trump $20 million to host the 2013 Miss Universe pageant in Moscow.

Agalarov and his son are currently under scrutiny because of their involvement in the June 2016 meeting at Trump Tower hosted by Donald Trump Jr.

Emin Agalarov, the pop musician son of the Russian tycoon, instructed his publicist, Rob Goldstone, to contact Donald Trump Jr. to set up the meeting. Goldstone told Trump Jr. that a “Russian government attorney” would be providing the Trump campaign with information about Hillary Clinton.

Trump’s comments on Wednesday stoked speculation that he is considering firing Mueller, a former director of the FBI. Trump also expressed frustration with Attorney General Jeff Sessions, whose recusal from the Russia probe paved the way for Mueller’s hiring in May.

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