Former Trump adviser Steve Bannon is being sued by a law firm claiming he has an outstanding balance of nearly a half-billion dollars in legal fees. The group represented Bannon in several high-profile litigations.

In a complaint filed in a New York state court Friday, the law firm Davidoff Hutcher & Citron (DHC) alleges that Bannon owed the firm $855,487.87, of which he paid only $375,000, leaving a balance of $480,487.87 that the firm is suing for.

"This action simply seeks payment of an outstanding bill for legal services rendered in the amount of $480,487.87 in addition to scheduling a hearing on the reasonable attorneys' fees DHC is contractually entitled to as the prevailing party in this litigation," the firm's lawsuit reads.

Bannon, 69, is a highly inflammatory conservative personality who has served as the head of Breitbart News and was a high-level strategist for former President Donald Trump's 2016 campaign. He became Trump's top adviser following his 2017 inauguration.

DHC has represented Bannon through many of his legal issues at the federal, state, and civil levels. When he was subpoenaed by the House Select Committee investigating the Jan. 6, 2021, Capitol attack in the last Congress, the firm defended him in court.

Bannon was subsequently charged in contempt of Congress for his refusal to answer a subpoena from the committee and is now appealing the four-month prison conviction and $6,500 fine.

DHC also represented Bannon throughout a federal investigation into charges that he defrauded donors who were sending money to build a wall at the southern U.S. border. The firm says it aided Bannon in obtaining a presidential pardon for the charges just before Trump relinquished office in 2021, according to the Associated Press.

Bannon has since pleaded not guilty to state charges brought up by the Manhattan district attorney's office stemming from the "We Build the Wall" fundraising campaign. He has been charged with conspiracy, money laundering, and scheming to defraud in what prosecutors described as a year-long scheme against donors.