Mueller just drew a direct line between Trump’s business and the Kremlin.

In January 2016, then-candidate Donald Trump rose to the defense of Russian President Vladimir Putin, who’d just been accused of likely ordering the assassination of a dissident former Russian spy in the UK.

“Many people say it wasn't him,” Trump said. “So who knows who did it?"

Days earlier, Michael Cohen, then an executive in Trump’s company, had personally called a Kremlin staffer to ask for help arranging financing for a Trump Tower in Moscow, according to a court filing released Thursday.

In a surprise courtroom appearance Thursday, Cohen pleaded guilty to lying to Congressional investigators about his communication with the Kremlin in the run-up to the 2016 election.

Cohen’s admission reveals that both Trump and the Kremlin downplayed the extent of their relationship at the time the campaign was already well underway — and kept up that charade long after Trump became president. Cohen's testimony also suggests Trump had a powerful financial incentive to win's Putin's approval, former prosecutors say.

“The significance of Cohen’s plea is motive — not Cohen’s motive, but Trump’s motive for deferring to Russia over and over again,” said Jens David Ohlin, Vice Dean at Cornell Law School. “The motive is money and business deals. This gives Mueller the last piece of the puzzle.”

On Thursday, Trump blasted Cohen in an impromptu press appearance, accusing him of lying to save himself from a lengthy prison sentence, and saying there was “nothing wrong” with pursuing a business opportunity in Russia, anyway.

Cohen’s confession should concern Trump, legal experts said. Thursday marked the first time special counsel Robert Mueller took direct aim at Trump’s private business dealings with Moscow in court. The criminal document also raises intriguing questions about who, particularly within Trump's family, Mueller may target next in his probe, former prosecutors said.

Read: A short history of Trump denying any connection to Russia

“A mountain of evidence now suggests that Trump’s praise of Putin has been to further his own financial interests, not to further the national security interests of the United States,” said Ilene Jaroslaw, a former federal prosecutor. “This indicates there’s a tremendous conflict of interest that Trump had as a candidate, and has as a president.”

On Thursday, Cohen pleaded guilty to lying to Congress under oath about his attempts to win Putin’s support for a big Moscow property deal in the midst of Trump’s campaign for the presidency.

Cohen’s guilty plea, which Trump’s lawyers claimed match up with the president’s written answers to questions from Mueller, contradicted Trump’s repeated public denials of having any business ties to Russia. And it undermined the Kremlin’s claim that it had received Cohen’s request for assistance, but never replied.

Cohen’s testimony sets a new backdrop for the infamous meeting in Manhattan in June 2016, in which the top brass of the campaign huddled together with a Russian lawyer with ties to the Kremlin who was billed as bringing dirt about Trump’s opponent, Hillary Clinton. The FBI determined that Russia’s cyber campaign to help Trump kicked into high gear soon after that.

Read: Michael Cohen pleads guilty to new charge in Mueller investigation

If Trump ever offered up any benefits to Russia in exchange for financial gain or material assistance for his campaign, that might open him up to a criminal bribery charge, said Seth Waxman, a former federal prosecutor.

“This is new evidence supporting the notion of a quid-pro-quo, in which Trump might have offered to reduce sanctions on Russian in exchange for benefits, including either the Moscow Trump Tower, or dirt on Hillary Clinton — or both,” Waxman said. The White House didn’t immediately return a request for comment from VICE News.

Joseph Moreno, a former prosecutor in the national security division of the Department of Justice, said that any synced-up lies from Cohen and the Kremlin would raise suspicions that the two sides may have been in closer alignment than they’ve claimed.

“This appears to be more circumstantial evidence of some degree of potential coordination between the Trump campaign and the Russian government,” he said.

Cohen confessed that his discussions about getting the Russian government to support the project continued as late as June 2016 — the month before Trump officially became the GOP presidential nominee.

And Cohen said he’d kept Trump — and Trump’s family members — better informed about those efforts than he’d previously admitted. In a 2017 appearance before the Senate Select Committee on Intelligence, Cohen had testified that he’d only discussed the Moscow project with Trump three times.

But on Thursday, Cohen said “three times” was a lie — it was more than that. And Cohen’s new “criminal information” document goes on to say that he also “briefed family members within the company about the project.”

That detail signals fresh legal jeopardy for Trump’s children, legal experts said, especially if they can be shown to have lied under oath about what they knew, and when they knew it.

“If I were any member of the Trump family, I’d be more worried today than I was yesterday about my own potential legal exposure,” Moreno said. “Whether or not pursuing a Trump Tower in Moscow was appropriate is one question. But whether Don Jr. was honest about it afterward could be where the real trouble lies.”

Cohen didn’t specify which family members in particular he briefed. But at least one of them — the president’s eldest son, Don Jr. — has testified he didn’t know about Cohen’s email to the Kremlin before it popped up in the news months later.

Read the new charges against Michael Cohen

Asked if he’d been aware that Cohen had sent an email to Putin’s press secretary, Dmitry Peskov, in January 2016, Don Jr. testified unequivocally: “No, I was not.”

Don Jr. admitted to being “peripherally aware” that the company was pursuing a property deal in Moscow, “but most of my knowledge has been gained since as it relates to hearing about it over the last few weeks,” he said on September 7, 2017.

Cohen’s startling admission comes as Mueller is widely believed to be preparing a final report on Trump’s links to Russia. A flurry of recent activity has suggested Mueller may finally be on the brink of unveiling some big answers.

“Mueller is tightening the circle around his main focus: Trump and Russia,” said Jill Wine-Banks, a member of the prosecutorial team during the Watergate scandal.

Trump himself appears to be feeling the heat. He’s attacked Mueller’s team on Twitter every morning for four days in a row, including retweeting an image of his own Deputy Attorney General, Rod Rosenstein — the man who appointed Mueller — locked up behind bars.

For now, Trump is denying the new allegations, and insisting there was “nothing wrong” with pursuing a business opportunity in Russia, anyway.

Chasing a hot business opportunity is no crime, legal experts agreed. But telling lies about it later to throw investigators off the trail could add additional evidence to charges of obstruction of justice, a central question Mueller has been tasked with answering, they said.

If Trump directed Cohen to lie to Congress, he could be criminally liable, Waxman said.

“Cohen has admitted that he lied to Congress, and it seems unthinkable that Trump and Cohen didn’t coordinate that story beforehand,” Waxman said. “Directing someone to lie to Congress is unambiguously obstruction and suborning perjury.”

Cover image: President Donald Trump listens to a question before traveling to the G20 Summit in Buenos Aires, on the South Lawn of the White House in Washington.