Michael Cohen exchanged hundreds of phone calls with an executive tied to a sanctioned Russian oligarch, according to newly unsealed federal search warrants that show the two sides were closer than either previously admitted.

Columbus Nova CEO Andrew Intrater and Cohen exchanged 320 phone calls and 920 text messages beginning on Election Day 2016, according to the warrants pursued by Special Counsel Robert Mueller’s office. Columbus Nova paid Cohen $500,000 for consulting work for what the company called “potential sources of capital and potential investments.” Intrater introduced Cohen to his cousin and business associate, the billionaire industrialist Viktor Vekselberg. Cohen was even added to Columbus Nova’s office security list.

The chatter between Cohen and Intrater was part of the network of relationships between Russian-linked interests and the former lawyer to President Trump.

Cohen’s attorneys did not immediately respond to requests to comment for this story. Intrater’s spokesperson downplayed the significance of the thousand-plus conversations between the two men.

“They were working together so of course texted and called each other. This was all known and investigated, and wasn't even deemed worthy of being included in the Special Counsel's report,” the spokesperson told The Daily Beast.

Intrater’s company, Columbus Nova, is an American-based asset management firm that counts as its biggest client the Renova Group, a company controlled by Vekselberg. Through Renova, Vekselberg owns interests across the world, including a minority stake in aluminum company Rusal, which was sanctioned by the U.S. government in 2018 for allegedly profiting from Russia’s “malign activities.” Vekselberg himself was sanctioned at the same time.

A source familiar previously told The Daily Beast that Vekselberg used Intrater as a “cut-out” for his access to Cohen—a claim Intrater and Vekselberg’s representatives strenuously deny to this day.

“The claim that Viktor Vekselberg was involved in or provided any funding for Columbus Nova’s engagement of Michael Cohen is patently untrue,” Richard Owens of the law firm Latham & Watkins previously said in a statement. “Neither Viktor Vekselberg nor anyone else outside of Columbus Nova was involved in the decision to hire Cohen or provided funding for his engagement.”

On its website, Columbus Nova insists that it is “an investment management company solely owned and controlled by Americans.” However, Securities and Exchange Commission filings from last year describe Columbus Nova as “the U.S.-based investment and operating arm of Mr. Vekselberg’s Renova Group of companies.”

Cohen was not paid directly by Columbus Nova, according to the warrants, but rather by a subsidiary known as Renova U.S. Management. The money was “wired through” Columbus Nova and the government said it was investigating why. It’s unknown if a conclusion was reached.

Vekselberg and Intrater met Cohen at least twice around the time he was hired by Columbus Nova, which has invested in numerous American media and technology firms, including Gawker Media, streaming-music pioneer Rhapsody, and a company called Tomfoolery Incorporated.

Vekselberg, Intrater and Cohen first huddled in Trump Tower in New York in January 2017 before Trump took office, Bloomberg News previously reported. Vekselberg then attended Trump’s inauguration with Intrater, who donated $250,000 to the president’s inaugural committee. (Vekselberg was questioned by federal agents working for Mueller during his investigation of Russian election interference.)

In March 2017, they met again at Intrater’s request. This time the subject appears to have been the Russian Union of Industrialists and Entrepreneurs, a business lobby based in Moscow which counts Vekselberg as a board member. “This is the organization that Victor [sic] was mentioning yesterday,” Intrater wrote to Cohen, according to the warrant. Bloomberg News previously reported the meeting was about a potential oil deal in the U.S. that did not materialize.

The FBI said in the warrants it was investigating whether the payments between the company tied to Vekselberg, who is under sanctions, were connected to Cohen delivering a plan to the White House to lift sanctions on Russia—including a previously unknown phone call between Cohen and Michael Flynn, the former national security adviser.

In late January 2017, the same month Columbus Nova started paying him, Cohen met with a Ukrainian lawmaker in New York promising a “peace plan” to end the conflict between Ukraine and Russia that led the U.S. to place harsh sanctions on Moscow in 2014.

The meeting was set up by Felix Sater, a Russian-American businessman who previously worked with Cohen on a project to build a Trump Tower in Moscow. Sater and Cohen began to exchange phone calls on January 5, according to the warrants, followed by a January 10 phone call between Cohen and Flynn.

Weeks later, Cohen met Trump in the Oval Office and then hand-delivered the plan to Flynn’s office, the New York Times previously reported.

Cohen is currently serving a prison term for unrelated financial and campaign-finance charges while Flynn awaits sentencing for lying to the FBI about his conversations with Russia’s ambassador to the U.S. regarding sanctions.