(CNN) Convicted former Trump campaign adviser George Papadopoulos has publicly contradicted Attorney General Jeff Sessions' sworn testimony to Congress, saying both Sessions and Donald Trump apparently supported his proposal that Trump meet with Vladimir Putin during the 2016 campaign, according to a court filing late Friday night.

"While some in the room rebuffed George's offer, Mr. Trump nodded with approval and deferred to Mr. Sessions who appeared to like the idea and stated that the campaign should look into it. George's giddiness over Mr. Trump's recognition was prominent during the days that followed," Papadopoulos' lawyers wrote in a court filing Friday. Papadopoulos' legal team said that he has shared with special counsel Robert Mueller his recollections of the March 31, 2016, meeting.

Sessions, when asked about that meeting at a House Judiciary Committee hearing, said that he "pushed back" on the idea of the Putin summit. CNN previously reported that Trump "heard him out," but Sessions shut down the idea of a Putin meeting, according to another adviser in the room , when Papadopoulos proposed the idea and offered to help execute it. Sessions' reaction was confirmed with another source who had discussed his role.

Justice Department spokesperson Sarah Isgur Flores declined to comment on Papadopoulos' assertions in Friday's filing and directed CNN to Sessions' testimony to the House Judiciary Committee on the issue.

The new description came in a criminal sentencing request Papadopoulos' legal team filed to a federal judge late Friday night -- the same day a lobbyist for Ukrainians admitted in court to criminal obstruction when he lied to Congress, and amid the President's intensifying public feud with Sessions.

Papadopoulos "was the first domino, and many have fallen in behind," his attorneys write Friday. "Despite the gravity of his offense, it is important to remember what Special Counsel said at George's plea of guilty: he was just a small part of a large-scale investigation."

Papadopoulos pleaded guilty to one count of lying to investigators last October. He asked the judge to sentence him to only probation that he has already served during the year since his plea, effectively allowing him to go free after his sentencing next week.

In a long narrative about his experiences, Papadopoulos' attorneys attempt in the sentencing memo to portray Papadopoulos as a young and eager Trump campaign staffer who found himself unaware of the broad investigation into Russian interference in the election when he lied to the FBI last year.

"Mr. Papadopoulos is ashamed and remorseful," Papadopoulos' attorneys wrote Friday. "His motives for lying to the FBI were wrongheaded indeed but far from the sinister spin the government suggests."

The Trump-Putin idea

Papadopoulos goes into specifics for the first time about how he floated the idea of a meeting between Trump and Putin at a campaign roundtable at the Trump International Hotel in March 2016. Donald Trump, then-Sen. Jeff Sessions and others attended the meeting.

About a month later, Papadopoulos learned that the Russians had "dirt" on Trump's opposition, Hillary Clinton, in "thousands of emails."

A Trump-Putin get-together never happened during the campaign.

Seeking probation

Prosecutors previously asked the judge to imprison Papadopoulos for up to six months, after he thwarted their early attempts to question a foreigner who may have known about Russian interference in the presidential campaign. The prosecutors' sentencing request focused more on the repeated lies Papadopoulos told about his contact with foreigners when he spoke to the FBI last year, and less about his interactions inside the Trump campaign.

In the filing Friday, Papadopoulos' lawyers lay out the image of an intellectually curious, successful and worldly man. They describe his scholarly work on energy policy in foreign countries and his interest in working for Trump in 2016.

Papadopoulos had "no experience with US and Russian diplomacy" when he started with Trump's campaign in 2016 -- yet eventually became one of the future president's foreign policy advisers.

In March that year, Papadopoulos met Joseph Mifsud, a European professor working in London who claimed to have connections to the Russian government, Papadopoulos's lawyers said. "Professor Mifsud paid young George little attention until learning of his position as one of Trump's foreign policy advisers," they write.

Papadopoulos' defense team also describes the first time he spoke to the FBI, months before the appointment of Robert Mueller as special counsel. Papadopoulos thought the FBI agents who came to his mother's house while he showered in early 2017 wanted to speak with him about Russian businessman Sergei Millian -- then enmeshed in the Trump dossier news coverage, the filing says. Millian at one point had pitched Papadopoulos "an opportunity," the lawyers write, giving few other details.

Media reports around that time identified Millian as a source of information in the dossier, though CNN has not confirmed his involvement nor many of the details in the dossier about alleged Trump-Russia collusion.

Millian has denied being a source for the dossier and says he does not have any compromising information about Trump.

Papadopoulos also spoke to the FBI investigators at that time about another foreign policy adviser for Trump with Russia connections, Carter Page, and about Mifsud and others.

Papadopoulos admits to lying to the FBI about his knowledge of the hacked Clinton emails.

"Out of loyalty to the new president and his desire to be part of the administration, he hoisted himself upon his own petard," Papadopoulos' attorneys write.

Papadopoulos is scheduled to be sentenced on September 7 by federal district judge Randy Moss in DC.