Singer Tulisa Contostavlos has been charged in connection with the supply of Class A drugs.
The Crown Prosecution Service (CPS) announced today that it had authorised the Metropolitan Police to charge the former X Factor judge with "being concerned in" the supply of drugs.
CPS London chief Crown prosecutor Baljit Ubhey said: "The Crown Prosecution Service has today authorised the Metropolitan Police Service to charge Tulisa Contostavlos, 25, with being concerned in the supply of Class A drugs
"This charge relates to an investigation by the Sun newspaper between early March 2013 and May 2 3 2013 which resulted in the supply of Class A drugs to an investigative journalist,"
"This decision to prosecute was taken in accordance with the code for Crown prosecutors.
"We have determined that there is sufficient evidence for a realistic prospect of conviction and that a prosecution is in the public interest."
Contostavlos will be required to appear before Westminster Magistrates' Court on December 19.
"This defendant is now the subject of criminal proceedings and has the right to a fair trial," Mr Ubhey said.
"It is extremely important that nothing should be reported which could in any way prejudice these proceedings."
Contostavlos was initially arrested in connection with the incident with 35-year-old musician Mike GLC on June 4.
She was officially dropped as a judge on X Factor days before her arrest, with Sharon Osborne returning to the show in her place.
A Scotland Yard spokesman said the singer had been charged alongside Michael Coombs, 35, of Enfield.
Contostavlos's lawyer Ben Rose said his client would be denying the charge and claimed she joined a line of celebrities who had had been used as "fodder by greedy newspapers".
In a statement he said: " Tulisa has been charged with a serious criminal offence to which she will plead not guilty.
"As has been widely reported this entire case has been manufactured by the Sun on Sunday and Mazher Mahmood, sometimes known as the fake sheikh. They spent a large amount of their readers' money in flying Tulisa and a number of her friends first class to Las Vegas. There Mahmood posed as a film producer offering her a £3million film contract.
"This case is not simply about drug supply. It is about the limits which we set on the conduct of journalists. The media have rightly been criticised in recent years for gross invasion into the private life of others.
"Tulisa is the latest in a long line of people who have been treated as fodder by greedy newspapers. This was a deliberate attempt to target a young woman who is all the more vulnerable because of her celebrity status.
"The law clearly forbids such conduct on the part of police. It is ironic that the police should rely on it when it is the work of a journalist.
"In due course Tulisa will give a full answer to these allegations in court."
A Sun spokeswoman defended the article, adding: "The Sun on Sunday's investigation into Tulisa Contostavlos was entirely justified in the public interest. It was undertaken by Mazher Mahmood, our award-winning journalist responsible for the football match-fixing investigation that has dominated the news recently.
"Ms Contostavlos is a self-described role model for young people and therefore has certain responsibilities. Throughout our investigation, our team followed the Press Complaints Commission Code and then handed over our dossier of evidence to the police.
"Following the police investigation, prosecutors have decided that there is a clear case to answer. It is right that this matter should go to court and be decided by a jury.
"Allegations about the conduct of this newspaper made by Ms Contostavlos' lawyers are entirely without foundation."