President Donald Trump's personal lawyer, Michael Cohen, contacted the drug giant Novartis after the 2016 election "promising access" to the new administration, and special counsel Robert Mueller later requested information from the company about the offer, a senior official inside Novartis told NBC News on Wednesday.

Cohen "contacted us after the new administration was in place," the official said. "He was promising access to the new administration." Novartis then signed a one-year, $1.2 million contract with Cohen.

A second company, AT&T, also revealed Wednesday that Mueller had inquired about a consulting deal it struck with Cohen after Trump took office "to help us understand" how the administration might approach policy issues of concern to the telecommunications industry.

The disclosures came after an attorney representing the adult-film actress who says she had an affair with Trump released a summary of bank transactions that he says shows payments from various companies to a company controlled by Cohen.

That lawyer, Michael Avenatti, said the transactions suggest that Cohen was "selling access to the president of the United States." Cohen and his attorney did not respond to a request for comment, and Trump attorney Rudy Giuliani told NBC News that the president was not involved in Cohen's business dealings.

According to Avenatti, at least $4.4 million flowed through Essential Consultants, the company Cohen created in October 2016 and then used to pay porn star Stormy Daniels $130,000 in hush money.

Among the transactions that Avenatti said he uncovered:

Columbus Nova, a U.S.-based firm with ties to Russian oligarch Viktor Vekselberg, made about $500,000 in payments between January and August 2017. In a statement, Columbus said it hired Cohen as a consultant "regarding potential sources of capital and potential investments in real estate and other ventures."

Novartis made at least four payments of just under $100,000 each in late 2017 and early 2018. In a statement, Novartis said it had an agreement with Essential Consultants, "focused on U.S. healthcare policy matters."

AT&T made four payments of $50,000 each to Essential in late 2017 and early 2018. In a statement, AT&T said it engaged the firm in early 2017 to "provide insights into understanding the new administration."

Korea Aerospace Industries made a $150,000 payment to Essential in November 2017. KAI said in a statement to Reuters that it had a contract with Essential for "legal consulting concerning accounting standards on production costs."

Avenatti did not disclose how he got the information or any other evidence that Cohen might be selling access to Trump. NBC News reviewed financial documents that appear to support Avenatti's accounting of the transactions involving the four companies.

Getting into a cab in Manhattan on Wednesday morning, Cohen told reporters that Avenatti's report "is inaccurate."

Later, his attorney filed a complaint letter with a federal judge that did not dispute the payments from Columbus, Novartis, AT&T and KAI but said smaller transactions that were listed by Avenatti were actually tied to different people named Michael Cohen.

In a statement, Novartis said it received an inquiry from investigators working for special counsel Robert Mueller, who is investigating Russian meddling in the 2016 election, about its dealings with Essential Consultants in November 2017.

"In February 2017, shortly after the election of President Trump, Novartis entered into a one-year agreement with Essential Consultants. With the recent change in administration, Novartis believed that Michael Cohen could advise the company as to how the Trump administration might approach certain U.S. healthcare policy matters, including the Affordable Care Act," the company said in a statement.

"The agreement was for a term of one year, and paid Essential Consultants 100,000 USD per month. In March 2017, Novartis had its first meeting with Michael Cohen under this agreement. Following this initial meeting, Novartis determined that Michael Cohen and Essential Consultants would be unable to provide the services that Novartis had anticipated related to U.S. healthcare policy matters and the decision was taken not to engage further.

"As the contract unfortunately could only be terminated for cause, payments continued to be made until the contract expired by its own terms in February 2018."

He contacted us after the new administration was in place. He was promising access to the new administration. A senior Novartis official

AT&T sent an email to its employees on Wednesday with details about its dealings with Cohen.

"In early 2017, as President Trump was taking office, we hired several consultants to help us understand how the President and his administration might approach a wide range of policy issues important to the company, including regulatory reform at the FCC, corporate tax reform and antitrust enforcement," said the email, which was obtained by NBC News.

"Companies often hire consultants for these purposes, especially at the beginning of a new Presidential Administration, and we have done so in previous Administrations, as well.

"Cohen was one of those consultants," the email continued. " Cohen did no legal or lobbying work for us, and our contract with Cohen expired at the end of its term in December 2017. It was not until the following month in January 2018 that the media first reported, and AT&T first became aware of, the current controversy surrounding Cohen."

In a later statement, AT&T said it gave information to Mueller about its contract with Cohen in November and December 2017, received no followup questions and consider "the matter closed."

Columbus Nova, in its Tuesday night statement, took issue with Avenatti's claim that it was controlled by Vekselberg, one of the richest men in Russia, with a multibillion-dollar oil and aluminum fortune.

Vekselberg is one of the oligarchs recently sanctioned by the U.S. Treasury Department. Separately, according to The New York Times, citing people familiar with the matter, he was searched and questioned by agents working for Mueller when he got off a plane in the U.S. earlier this year.

Russian President Vladimir Putin, left, with Renova CEO Viktor Vekselberg during an award ceremony at the Kremlin on Jan. 26, 2017. Alexei Druzhinin / Sputnik

An attorney for Columbus Nova, where Vekselberg's cousin Andrew Intrater is the CEO, said claims Vekselberg "used Columbus Nova as a conduit for payments to Michael Cohen are false. The claim that Viktor Vekselberg was involved or provided any funding for Columbus Nova's engagement of Michael Cohen is patently untrue."

No one has been charged with a crime in connection with the Essential Consultants transactions, but Avenatti said the large payments, their timing and the disparity of the companies' interests are red flags of a pay-to-play scheme by a man often described as Trump's "fixer."

"We now have multiple different things supposedly that Michael Cohen was doing for all these companies. Now we hear from Novartis that he was hired on health care matters — evidently he's a doctor," Avenatti said facetiously on MSNBC's "Morning Joe."

"One of the companies mentioned they hired him for real estate matters — he's a real estate agent? Another company stated that they hired him for accounting advice, evidently he's an accountant. So he's a lawyer, a doctor, an accountant, and a real estate agent.

"I'm just a lawyer. I'm not that bright, I guess," Avenatti added.

"Where did the money go?" he asked. "Did all of it go to Michael Cohen? Did some of it go back to the Trump organization? Did some of it ultimately find its way back to the president?"

NBC News asked Cohen and the various companies for comment on Avenatti's accusation about the purpose of the payments but none had an immediate comment.

In a brief telephone interview, Giuliani said "the president is not involved in any way [with Cohen's business dealings] either before or after he was president."

Cohen is the subject of an investigation by the U.S. attorney's office in Manhattan, and the FBI raided his law office and hotel room last month, seeking information about the $130,000 payment he made to porn actress Daniels, whose real name is Stephanie Clifford.

Adult-film actress Stephanie Clifford, also known as Stormy Daniels, speaks outside U.S. District Court in Manhattan with her lawyer, Michael Avenatti, on April 16. Eduardo Munoz Alvarez / AFP — Getty Images file

The FBI has also monitored his phone calls with a pen register, meaning that the incoming and outgoing phone numbers were recorded but not the content of the calls.

Clifford claims she had a sexual affair with Trump a decade ago; the White House has said Trump denies it. In the fall of 2016, as the election approached, Cohen brokered a non-disclosure agreement with Clifford and wired her $130,000 from Essential Consultants' account at First Republic Bank.

Cohen has long maintained that he put up the money and that he was not reimbursed by the Trump campaign or by the Trump Organization. But one of Trump's lawyers, former New York City Mayor Rudolph Giuliani, revealed last week that Trump had paid the $130,000 back to Cohen, providing dueling accounts of when Trump learned about the transaction.

Clifford has sued Trump and Cohen, claiming the non-disclosure agreement is invalid because he never actually signed it, and she has also sued the president for defamation for casting doubt on her account of being threatened by an unknown man several years ago to keep quiet about Trump.