R. Kelly files notice to appeal conviction, court documents show

R. Kelly has formally informed a federal court that he intends to appeal his conviction on racketeering charges.

On Monday, Kelly's defense attorney, Jennifer Bonjean, filed a notice of appeal, which did not say on what grounds Kelly intended to challenge the verdict and the 30-year prison sentence he was given after he was found guilty of leading a criminal enterprise that recruited women and girls for sex.

Kelly's conviction in September included charges of racketeering and violating the Mann Act, a sex trafficking law, including having sex with underage girls. The charges also included a bribery scheme involving a public official to get a fake ID for the late pop singer Aaliyah so the two could get married when she was 15 and he was 27.

Kelly believed Aaliyah was pregnant at the time, prosecutors wrote in a sentencing memo.

After Kelly was sentenced last month, Bonjean announced she would be appealing the case, maintaining that he is not an abuser. Kelly was temporarily placed on suicide watch following the sentencing.

"Mr. Kelly is fine," a lawyer for Kelly told reporters outside the Brooklyn Federal Courthouse after the sentencing. "We believe that this enterprise was overcharged."

The defense cast many of R. Kelly's victims as groupies who willingly went along with Kelly's sexual demands and said prosecutors misapplied racketeering statutes to Kelly's case.

"Invigorated by an influential social movement determined to punish centuries of male misbehavior through symbolic prosecutions of high-profile men, the government brought a RICO prosecution against the Defendant that was 'absurdly remote' from the drafters' intent," a previous defense filing said.

U.S. Attorney Breon Peace, the prosecutor in the case, and Steve Francis, acting executive associate director of U.S. Homeland Security Investigations, attributed the outcome of the case to the bravery of the victims who came forward, labeling Kelly as a predator who was able to continue his crimes for more than 30 years.

Bonjean did not immediately respond to ABC News' request for comment.