WASHINGTON -- Sen. Tom Coburn played a more active role than previously known in the negotiations between ex-Sen. John Ensign (R-Nev.) and his former aide, Doug Hampton. The extent of the Oklahoma Republican's involvement is made clear in a report released Thursday by the Senate Ethics Committee that accuses the former senator of serious criminal violations.

Ensign resigned from the Senate earlier this month, but had admitted in 2009 to having an affair with Cynthia Hampton -- a past campaign aide and the wife of Doug Hampton. During a two-year inquiry into possible violations by Ensign, the Senate Ethics Committee found that he violated campaign finance laws and obscured justice to cover-up his affair.

Coburn, a friend of Ensign’s who confronted him about the adultery, became involved as an intermediary in negotiations between Ensign and Doug Hampton. The former aide sought money from Ensign in spring 2009. Coburn negotiated the payment to Doug Hampton down from $8 million to about $2.8 million, according to the report.

The Oklahoma Republican's involvement in the cover-up of the affair could lead to uncomfortable questions for the senator and his party going forward. While Ensign left the Senate hastily last week, Coburn remains an active figure.

The report provides extensive details of the Coburn's collaboration. He spoke to Hampton’s attorney, Daniel Albregts, three times on May 22, 2009, to discuss money Ensign planned to give the Hamptons. Coburn first said he wanted to “help Doug out” because he liked him and felt bad about what had happened, the report says. The Oklahoma Republican asked Albregts to find out what Hampton needed to start over.

According to the report, Albregts called about an hour later, interrupting Coburn from mowing his lawn on a tractor. The lawyer told the senator that Hampton had proposed $8 million to resettle his family and find a new job. Albregts told the Ethics Committee that Coburn countered, calling the figure “absolutely ridiculous.” Instead, Coburn reportedly said the Ensigns should purchase the Hampton’s home and give them some money to live off of while they looked for new jobs.

In a third call, Albregts proposed payments for the Hamptons of $1.2 million for their home and $1.6 million for relocation, the report says. During that five-minute call, Coburn said he thought that was reasonable and that he would take the request to Ensign. The former senator from Nevada, however, refused to pay that total.

Coburn denied that he served as a negotiator when he testified for the report, but acknowledged he spoke to Hampton’s attorney, Albregts, in May 2009. The Oklahoma Republican told the Ethics Committee that he was simply planning to pass along information to Ensign.

In 2008, the senator was one of the men to confront Ensign about ending his affair with Cynthia Hampton, according to the report. Cobburn, along with C Street Christian fellowship's evangelical leaders Tim Coe, David Coe and Marty Sherman, talked to Ensign and Doug Hampton at their group house on February 14, 2008. The Coes and Sherman are involved with The Family, a Christian group the C Street House is affiliated with.

“Senator Ensign was told that the affair had to stop,” the report says. “Mr. Hampton was very emotional during the meeting, and at one point got very close to a physical confrontation with Senator Ensign. Senator Coburn asked Mr. Hampton to leave, stating 'we’ll take it from here. We'll take care of this.'”

Eventually, Tim Coe went to the ex-senator's father, Michael Ensign, to stop the affair. Tim Coe reportedly said that Coburn “was not big enough” for the job. The elder Ensign said he would handle it, according to the report.

Coburn staged a second intervention for the Nevada politician about a month after the Feb. 14, 2008 talks.

“Senator Coburn stated, ‘I can’t take this anymore. I’ve got to tell these guys.’ Mr. Sherman and others, including Members of Congress, went to Senator Ensign’s bedroom at the C Street Center and confronted him about the affair,” the report says. The adulterous relationship continued until later that year.

When the affair ended, Coburn was part of the “team” that discussed relocating the Hamptons to Colorado and providing them with money for their transition, the report says.

“According to Mr. Coe, 'Doug was more confident talking to Senator Coburn about finances than he was us,' and Mr. Hampton thought Senator Coburn 'could deliver John’s father,' who was wealthy,” the report says. “Senator Coburn played a 'support role,' and encouraged Senator Ensign to consider the plans developed by Mr. Coe and others regarding transition and separation.”

Ensign’s father eventually gave the Hamptons $96,000 as a gift, which Ethics Committee charges was in violation of campaign finance laws.

A spokesman for Coburn did not immediately reply to requests for comment.