Former X Factor judge Tulisa Contostavlos has pleaded not guilty to a charge of being involved with the supply of Class A drugs.
The N-Dubz star was arrested along with 35-year-old musician Mike GLC, also known as Michael Coombs in June following an undercover sting set up by a Sun reporter.
She is accused of arranging an £860 cocaine deal for reporter Mazher Mahmood, the so-called "Fake Sheikh", at the upmarket Dorchester Hotel in central London in May.
She was said in court to have played a "significant role" by putting Mahmood in touch with Coombs.
Contostavlos of Friern Barnet, north London, appeared alongside Coombs, of Enfield, north London, at Westminster Magistrates' Court. He also denied supplying the drug.
The Young hitmaker was forced to disclose her address in open court despite a request by her lawyer to avoid "unwanted visitors".
Chief magistrate Howard Riddle ruled that the address had to be given after he considered the application along with representations by prosecutor Emma Scheer and the Press Association.
The singer then told the court: "Just to let you know, after it being read out, in the next month or so I might have to move to a new address."
Both defendants were granted unconditional bail. They are scheduled to appear at Southwark Crown Court in central London on 9 January.