A woman sacked by UK intelligence after a top secret memo was allegedly leaked to the press has been charged with breaching the Official Secrets Act.
GCHQ is the home of Britain's intelligence-gathering operations
Katharine Teresa Gun, 29, was first arrested in March after a memo from US monitoring body the National Security Agency was sent to the Observer.
Ms Gun has said any disclosures she may have made were "justified".
She was charged at Cheltenham Police Station and bailed to appear at Bow Street Magistrates on November 27.
Surge in eavesdropping
The January 31 memo received by the Observer reportedly said the NSA had begun a "surge" in eavesdropping on UN Security Council countries about to vote on action in Iraq.
Officials from Angola, Cameroon, Chile, Bulgaria, Guinea and Pakistan all had their phones tapped in what the newspaper described as a "dirty tricks" operation.
The author of the memo was supposedly Frank Koza, Defence Chief of Staff (Regional Targets) at the agency.
Under Section 1, of the 1989 Officials Secret Act it is an offence to disclose security and intelligence information without the correct authorisation.
Ms Gun has justified the disclosures saying in a statement that she had "only ever followed her conscience".
"No-one has suggested (nor could they), that any payment was sought or given for any alleged disclosures," she said in the statement released through her lawyers.
Disclosures "exposed wrongdoing"
Ms Gun claimed any alleged leaks exposed "serious illegality and wrongdoing on the part of the US Government" and were designed to prevent "wide-scale death and casualties among ordinary Iraqi people and UK forces".
A spokesman for the Government's communications headquarters at Cheltenham confirmed Ms Gun had worked for the organisation but said it "was a matter for the Metropolitan Police" who charged her.
A spokesman for Liberty claimed the case was likely to put the legality of the whole war on Iraq on trial.