WASHINGTON — The former national security adviser Michael T. Flynn discussed sanctions at length with a Russian diplomat in late 2016, according to transcripts declassified on Friday that appear to bolster earlier assertions that Mr. Flynn misled Vice President Mike Pence and F.B.I. agents about those conversations.
The transcripts have become a conservative cause, and the Justice Department threw the weight of the Trump administration behind it in moving recently to throw out Mr. Flynn’s guilty plea to a charge of lying to agents in the Russia investigation about the calls. President Trump has said Mr. Flynn was badly treated, part of Mr. Trump’s campaign to escalate unfounded accusations that the government’s investigation was a plot to undermine him.
Mr. Flynn has said he does not remember talking in late 2016 with the Russian ambassador to the United States at the time, Sergey I. Kislyak, about sanctions newly imposed by the Obama administration as punishment for Russia’s election meddling. But the transcripts showed that the sanctions were the central discussion point between the men.
The new director of national intelligence, John Ratcliffe, declassified the transcripts, and two Republican senators, Charles E. Grassley of Iowa and Ron Johnson of Wisconsin, who pushed Mr. Ratcliffe and his predecessors to share the material with Congress and make it public, released them. The senators held up the 27 partly redacted pages as evidence for their accusations that the F.B.I. abused its power in investigating Mr. Trump’s associates.
The declassification was itself highly unusual; intercepted calls are some of the government’s most closely guarded secrets. The documents also revealed highly sensitive F.B.I. abilities, showing that the bureau was able to monitor the phone line of the Russian Embassy in Washington even before a call from Mr. Kislyak connected with Mr. Flynn’s voice mail.
Mr. Ratcliffe’s predecessor Richard Grenell had begun aggressively declassifying documents around the Flynn case in recent weeks, deeming his efforts acts of transparency. He has said that the material should have been made public earlier to discredit the inquiries into Russia’s ties to the Trump campaign.
Intelligence experts have bristled at the disclosures of conversations intercepted as part of spy agencies’ routine eavesdropping on foreign officials. Disclosing the specifics of any conversations threatens to show Russia and other adversaries the United States’ wiretapping abilities.
Some former officials have also said that the disclosures set a precedent for future administrations to selectively release material when it is politically beneficial.
Mr. Flynn was the only former White House official to plead guilty in the special counsel investigation into Russia’s election interference and possible ties to Trump associates, and the charge grew out of his calls with Mr. Kislyak. The controversy over the Justice Department’s move to withdraw the charge against Mr. Flynn stems in part from law enforcement officials’ conclusion that the calls were immaterial to the inquiry.
The men spoke three times in late December 2016 and again on Jan. 12, 2017, according to the transcripts. Mostly, they discussed the Russian response to the Obama administration’s punishment for election interference: expelling 35 Russian diplomats, closing two estates in the United States used for Russian intelligence and imposing sanctions and other penalties.
According to the call transcripts, Mr. Flynn angled for a better relationship between the United States and Russia and for renewed cooperation. He dismissed Russia’s operations to interfere in the American election — stealing Democratic emails and sowing division on social media — as “this current issue of the cyberstuff.”
In one of the calls, Mr. Flynn asked that Moscow avoid retaliating in response to the sanctions.
“Don’t go any further than you have to because I don’t want us to get into something that has to escalate on a, you know, on a tit for tat,” Mr. Flynn said. “You follow me, Ambassador?” Mr. Kislyak said he understood.
Two days later, Mr. Flynn complimented President Vladimir V. Putin of Russia for rejecting any retaliation. Mr. Flynn told Mr. Kislyak that he appreciated “the steps that, uh, your president has taken. I think that it is — was — wise.”
Mr. Kislyak said that “cold heads” prevailed, slightly mangling the phrase, and that the Kremlin determined that the Obama administration punishment was “targeted not only against Russia, but also against the president-elect.”
“I just wanted to let you know that our conversation was taken with weight,” Mr. Kislyak told Mr. Flynn.
The F.B.I. interviewed Mr. Flynn weeks later. According to prosecutors, Mr. Flynn told agents that he did not ask that Russia refrain from escalating in response to the sanctions and that he did not remember the follow-up conversation with Mr. Kislyak.
Critics of the Trump administration seized on the transcripts’ discussions as evidence that Mr. Flynn was undermining existing Obama administration foreign policy. They argued that the Constitution allows for only one president at a time and that if an incoming administration begins foreign policy negotiations before taking office, it confuses the issue of who holds power.
“These transcripts clearly demonstrate that Lt. Gen. Michael Flynn lied to the F.B.I. and the vice president,” said Representative Adam B. Schiff, Democrat of California and the chairman of the House Intelligence Committee.
He added that Mr. Trump and his allies have promoted “conspiracy theories to distract and rewrite history, as the true facts and history are so damning.”
Conservatives have said that Mr. Flynn did nothing wrong and that it was in the public interest for him to represent the views of the incoming administration. Attorney General William P. Barr has called Mr. Flynn’s request that Russia avoid retaliation “laudable.”
Mr. Grassley said that the transcripts showed “shenanigans and abuses of power” at the F.B.I. in investigating Mr. Flynn. “After all the screw-ups and malicious behavior by F.B.I. and D.O.J. officials during the Russia investigation, we simply cannot take them at their word anymore,” he said.
After cooperating extensively with the special counsel investigation, Mr. Flynn reversed course this year, moving to withdraw his guilty plea and saying he did not remember whether he discussed sanctions with Mr. Kislyak. After the Justice Department’s extraordinary step this month to drop the case, a federal judge began to scrutinize the request.
Mr. Flynn also admitted he had violated foreign lobbying laws because of work for the Turkish government but was not charged on those violations as part of his agreement to cooperate with prosecutors.
He had admitted to lying to the F.B.I. about talking to Mr. Kislyak about Russia’s vote on an impending United Nations resolution to condemn Israeli settlements in the West Bank.
Mr. Kislyak promised to “postpone the vote and to allow for consultations,” according to the transcript. Mr. Flynn responded: “OK. That’s good.”
The documents also offered further evidence that Mr. Trump’s advisers saw the weeks from his November 2016 election victory until Inauguration Day as an opportunity to seek common cause with Russia on the issue of international terrorism — and possibly to try to broker an end to the yearslong civil war in Syria.
Mr. Flynn said during the calls that he did not want the sanctions to scuttle a potential partnership in the Middle East. Mr. Flynn and Jared Kushner, Mr. Trump’s son-in-law and senior adviser, met in November 2016 with Mr. Kislyak at Trump Tower in Manhattan to discuss back-channel communications to the Kremlin about the war in Syria.
According to the report of Robert S. Mueller III, the special counsel investigating Russian interference, Mr. Kushner expressed a desire during the 30-minute meeting for the new administration to “start afresh with U.S.-Russian relations.” The men also discussed American policy toward Syria, and Mr. Kushner made a startling proposal to use “secure facilities at the Russian embassy” to communicate. Mr. Kislyak rejected the idea, according to the report.
Mark Mazzetti contributed reporting.