Former Donald Trump campaign official Mike Roman is cooperating with prosecutors from special counsel Jack Smith's team in the ongoing criminal probe related to efforts to overturn the 2020 election, two sources familiar with the matter told CNN.

One of the sources said that the agreement, known as a proffer agreement, means that Roman may not have to appear before the grand jury but could instead speak to prosecutors in a more informal setting. Under such an agreement, prosecutors generally agree not to use those statements against them in future criminal proceedings.

Roman, who received a grand jury subpoena months ago and had his phone seized, was involved in efforts to put forward slates of fake Trump electors following the 2020 election.

Investigators have recently zeroed in on the efforts to put forward alternate slates of electors in seven states Trump lost and the role of lawyers who were working for the former president after the 2020 election, multiple sources have said.

Until recently, Roman had little substantive contact with the Justice Department since his phone was seized and only recently began to engage in conversations about his possible cooperation, according to one of the sources.

The timing of those discussions coincides with last week's grand jury appearance by Roman's former deputy, Gary Michael Brown.

The New York Times previously reported that Roman was in talks with prosecutors about a potential proffer agreement.

The House select committee that investigated January 6, 2021, interviewed Roman -- a senior adviser to Trump's 2020 reelection campaign and tasked with Election Day operations -- as part of its inquiry.

Speaking to House investigators, Roman invoked his Fifth Amendment right against self-incrimination for the committee's questions about his efforts after the election. However, he did answer some of the committee's questions about his activities ahead of Election Day.

Roman told investigators that when it came to former Trump attorney Rudy Giuliani, "I don't believe I had any interaction with him before the election."

But when asked about his interactions with Giuliani after Election Day, Roman said: "On the advice of counsel, I assert my constitutional privilege under the Fifth Amendment and respectfully decline to answer the question."

Giuliani has met voluntarily with Smith's team, CNN previously reported.