Everything President Trump’s former national security adviser Michael Flynn discussed last December with the Russian ambassador to the U.S.—everything that led to his dramatic guilty plea and cooperation agreement Friday with special counsel Robert Mueller—he did with the involvement of the presidential transition team.

That’s the story told in the most important document (PDF) Mueller released on Friday that could have intensified the president’s own legal liability: Flynn’s stipulation of the facts underlying his December 2016 conversations with then-Russian Ambassador Sergey Kislyak. At least one of those two conversations Flynn undertook at the direction of a “very senior” transition official, the stipulation says.

The documents do not say who directed Flynn to discuss sanctions with Kislyak—a conversation Flynn later reportedly lied about to Vice President Mike Pence, a lie that was the stated reason that Trump fired Flynn in February. But Flynn’s statement, following his Friday guilty plea and agreement to cooperate with Mueller’s probe, shows that the transition team, at Trump’s Mar-a-Lago resort, was informed at every stage of his discussions with Kislyak.

And that itself raises new questions about what Pence, who ran the presidential transition and publicly affirmed that Flynn never talked to Kislyak about Russia sanctions, actually knew.

Pence’s attorney did not immediately respond to a request for comment. A spokesperson for the presidential transition team’s legal team also didn’t immediately respond.

Did Flynn Go to Jared?

But, according to a former Justice Department official, that “very senior” official named by Mueller is probably in substantial legal jeopardy. If the “very senior” official lied to Mueller’s team about directing Flynn to reach out to the Russians, then Flynn would be poised to testify about that lie.

Flynn said he is cooperating with Mueller’s team. It’s unlikely Mueller would have cut him a deal unless Flynn could implicate someone even more important than himself. And that person is likely the “very senior” official who Flynn alluded to in his statement, according to the former DOJ official, who added that Jared Kushner best fits the description.

On Dec. 28, President Barack Obama put new sanctions on Russia for its election interference. Kislyak, per the factual stipulation, contacted Flynn that day. The next day, Dec. 29, Flynn “called a senior official” on the transition team, not named in the documents, “to discuss what, if anything, to communicate to the Russian ambassador about the U.S. sanctions.”

Flynn and the anonymous senior official then discussed the impact the sanctions would have on “the incoming administration’s foreign policy goals,” and the transition team’s desire not to have Russia “escalate the situation.” Flynn called Kislyak back “immediately” after discussing the matter with the senior official, the stipulation says, to convey Team Trump’s preference for a measured Russian response. Russian President Vladimir Putin publicly stated on Dec. 30 that he would not substantially retaliate. Trump then tweeted that day: “Great move on delay (by V. Putin) - I always knew he was very smart!”

It was not the end of the Kislyak-Flynn correspondence.

The next day, Dec. 31, Kislyak again called Flynn to convey Russia’s lack of retaliation “in response to Flynn’s request”—which was, in substance, a Trump transition team request. Flynn subsequently talked to “several members of the Trump transition team about Flynn’s conversations” with Kislyak. At this point, more than one Trump transition official knew about their discussions.

Why did Kislyak know that Flynn was the person on the Trump team to discuss sanctions with? Perhaps because of Flynn’s infamous 2015 paid visit to Moscow for the Russia Today gala, where he sat at Putin’s table. But it might also be, per the factual stipulation, because Kislyak and Flynn had a different discussion the previous week.

At issue then was a UN Security Council resolution critical of Israel. The factual stipulation said a “very senior member of the Presidential Transition Team”—also unnamed—“directed Flynn to contact officials from foreign governments, including Russia” to feel them out on it. Though the Obama administration was still in office, this “very senior” official wanted Russia to “delay the vote or defeat the resolution.”

Flynn, on or around Dec. 22, called Kislyak and asked the Russian government to punt or defeat the resolution. The next day, Kislyak called Flynn and essentially said no—but in the way that, diplomatically, could be conceived as a minor victory, since it left open the possibility of Russia delaying the resolution.

“If it came to a vote Russia would not vote against the resolution,” Mueller and Flynn agree was the substance of Kislyak’s response. The resolution was adopted that day (PDF).

New Questions About Pence

On Jan. 15, transition chief Pence told CBS News that contacts between Team Trump and Team Putin were “bizarre rumors” and that Flynn did not discuss sanctions with Kislyak—even though Flynn expressly had and communicated that with other members of the transition.

“Actually it was initiated when on Christmas Day, he [Flynn] had sent a text to the Russian ambassador to express not only Christmas wishes but sympathy for the loss of life in the airline crash that took place,” Pence told CBS, citing what Flynn had told him. The Christmas texts do not appear in the Mueller-Flynn factual stipulation.

“It was strictly coincidental that they had a conversation, they did not discuss anything having to do with the United States’ decision to expel diplomats or impose censure against Russia,” Pence said.

The factual stipulation, again, names none of the multiple Trump transition officials who were knowledgeable about the Kislyak conversations. Kushner, according to earlier reporting, was also in touch with Kislyak in December 2016. Mueller reportedly interviewed Kushner last month.

The Daily Beast reported on Friday that Trump himself has privately fumed that Flynn has “turned on me.” Trump has repeatedly insisted that allegations of collusion with Russia are partisan apparitions and that he himself is not under investigation. He has publicly flirted with firing Mueller, and The New York Times reported he pressured GOP members of the Senate intelligence committee investigating Kremlin involvement in the 2016 election to quickly wrap up their probe.

“Members of Congress from both parties must make clear that those actions would be fundamentally unacceptable and incompatible with the rule of law,” Mark Warner, the senior Democrat on the Senate intelligence panel, warned in a Friday statement.