The Northern Ireland Prison Service has decided to transfer all but four prisoners from the high-security Maze prison to Maghaberry jail near Moira, Co Armagh, by the end of this month, according to local newspaper reports.
Since the mass release of paramilitary prisoners at the end of July only 14 prisoners have remained in the Maze.
Seven are understood to be republican, five loyalist and two others, guarded by 120 prison officers.
Loyalist politicians have accused the Prison Service of bias as all four remaining prisoners are understood to be republicans.
Maghaberry is known to have harsher conditions than the Maze and treats inmates as ordinary rather than political prisoners. Furthermore, they are not segregated according to their paramilitary grouping as in the Maze.
The Progressive Unionist Party's prison spokesman, Mr William Smith, said he was angry at the news.
"By the end of the month there will be one UVF inmate left and we are pressing for him to remain at the Maze. What is the difference between four or 10 prisoners at the Maze? This is not acceptable," he added.
A Prison Service spokesman said it would not discuss "operational matters" affecting the movement of prisoners. Sources, however, confirmed the transfer to Maghaberry would take place by the end of August.