The ruling in Belfast this week that the "Real IRA" is not a proscribed organisation will be challenged in the appeal court, the British Attorney General said today.
Lord Goldsmith confirmed he would seek to overturn a decision made on Wednesday by Mr Justice Paul Girvan at Belfast Crown Court.
"The Attorney General considers the point of importance and one which ought to be tested in the Court of Appeal in Northern Ireland," said a statement from Lord Goldsmith's London office.
"He has therefore decided to ask the Court of Appeal to consider this ruling..."
Clearing four men of charges of "Real IRA" membership, Mr Justice Girvan said that because the organisation was not specifically named in a list of proscribed groups in the Terrorism Act 2000 it was not illegal.
He rejected the prosecution argument that the mainstream IRA's listing applied equally to its dissident off-shoots.