The loyalist convicted of murdering Belfast solicitor Pat Finucane has been told he does not qualify for early release under the Good Friday Agreement.
Ken Barrett was convicted of the murder in September
Ken Barrett was sentenced to 22 years in September after pleading guilty to the 1989 murder, but it was thought at the time he could be freed by March.
But he has now been told he does not qualify because he is not serving his sentence in Northern Ireland.
His solicitor says his client is appealing against the decision.
Mr Finucane was shot dead by the loyalist Ulster Defence Association.
The killing was one of the most controversial of the 30 years of the Troubles in Northern Ireland, mainly because of the allegations of collusion between loyalist paramilitaries and members of the security forces.
After conviction, Barrett, 42, was transferred to London's Belmarsh Prison because of threats against him.
The decision by the Sentence Review Commission which runs the release programme means he may be forced to serve the minimum 22 years behind bars
recommended when he pleaded guilty to murder.
His solicitor Joe Rice claimed that the body had made an error.
"They misdirected themselves in law and effectively didn't give him an opportunity to have his application fully and properly considered," he said.
Pat Finucane was shot dead by loyalist paramilitaries
"Ken Barrett continues to be a sentenced prisoner under the regime applicable
to Northern Ireland.
"He's still very much part and parcel of the Northern Ireland criminal
"We now have instructions from him by telephone that he wishes to appeal this
It is expected that a three-member panel from the Commission will be asked to
review the decision.
Under the early release programme, terrorists convicted before the April 1998
Good Friday Agreement who had served at least two years in prison were
considered for release.
The scheme, which saw some of Northern Ireland's most notorious killers walk
free, is one of the most controversial strands of the peace process.