R Kelly has denied the charges

Florida prosecutors charged Mr Kelly with 12 counts of possessing child pornography because of pictures showing him allegedly having underage sex.

But Judge Dennis Maloney said the warrant used to seize the pictures was based on insufficient evidence.

He said the digital photographs would be inadmissible in court.

Prosecutors have not yet decided whether they will appeal or drop the charges against the singer, who has had hits with songs such as I Believe I Can Fly.

"I don't believe the judge has entered his written order. We'll wait to examine that," said state attorney's spokesman Chip Thullbery.

'Faith in our system'

Mr Kelly has consistently denied the charges, said to have taken place in January 2003, and released a statement from his Chicago home, where he is out on bail awaiting trial.

"I've always had faith in our system of justice, and I do believe justice was done here today," he said.

"As I've said before, I am confident that when all the facts are brought out, people will see that I'm no criminal."

Mr Kelly would face up to 60 years in jail if found guilty of the charges.

The singer also faces charges in Illinois stemming from another incident from 2000, a videotape which allegedly showed him having sex with a girl police said was 14 at the time.

The singer denied he was the man seen on the tape.