Former U.S. Sen. Bob Kerrey resigned last week from the board of Monolith, a Nebraska-based clean energy startup, after renewed attention to his past interactions with convicted sex offender Jeffrey Epstein.

Kerrey, a Democrat who served two terms in the Senate and previously as governor of Nebraska, confirmed to The New York Times that he stepped down Friday, saying the resurfaced emails would make it “difficult for them to succeed.” He had been serving as chairman of Monolith’s board of directors.

The Justice Department recently released files related to Epstein that included references to Kerrey’s communications with the disgraced New York financier more than a decade ago. The records indicate that Kerrey and Epstein met twice in early 2013 and exchanged emails during 2013 and 2014.

At the time of the meetings, Kerrey was serving as president of The New School in New York City. Epstein had already pleaded guilty in 2008 to charges related to solicitation of prostitution involving a minor.

According to the email exchanges, Kerrey declined one invitation in February 2013 to meet Epstein at his home when others, including business leaders, were expected to attend, but wrote, “Invite me again!” In May of that year, Kerrey sent a message thanking Epstein for breakfast, writing that it was “great being with you.” The correspondence shows additional attempts to arrange lunches and dinners that would have included high-profile figures such as filmmaker Woody Allen, former Israeli Prime Minister Ehud Barak, and technology investor Peter Thiel.

Kerrey told the Times he recalls one meeting with Epstein and acknowledged there may have been others he does not remember. “I will offer no defense of my meetings with Jeffrey Epstein,” he said, adding that had he known then what he knows now, he would not have agreed to meet.

He also emphasized that the focus should remain on Epstein’s victims, stating that he was not among them and that the women abused by Epstein and his associates as minors are the true victims in the case.

A spokeswoman for The New School said the institution reviewed the correspondence and found no indication the interactions were connected to school business. She added that the university regrets any association with Epstein, describing his crimes as reprehensible.