A little-known attorney is reportedly expected to take on a prominent role on President Trump's legal team.

Andrew Ekonomou - a former prosecutor with a doctorate in medieval history - will assume a more central role, Reuters reported.

Ekonomou has been helping Jay Sekulow in representing Trump in special counsel Robert Mueller's investigation into Russian election interference and possible ties between Trump's presidential campaign and Russia.

Ekonomou has not worked on high-profile cases such as the Russia investigation, however, according to Reuters.

He said in an interview that he has been "tested plenty of times."

"Just because you're not a Beltway lawyer doesn't mean you don't know what you're doing," he said.

Ekonomou's more prominent role comes after the abrupt resignation last week of John Dowd.

A report earlier this week said two more leading attorneys have rejected an offer to represent Trump.

Tom Buchanan and Dan Webb, who are partners at Winston & Strawn, told The Daily Beast that the president reached out to them to see if they would join his legal team. They turned down the offer, citing business conflicts.

Former U.S. Solicitor General Theodore Olson also rejected a reported job offer to join Trump's legal team.

The White House said Sunday that conflicts would prevent Washington, D.C.-based lawyer Joseph diGenova and Victoria Toensing from joining as well.

Trump is reportedly seeking to shake up his legal team amid frustrations within the White House over Mueller's probe, which has cast a cloud over the administration for more than a year.