A dissident faction of the UDA is believed to have started the process of decommissioning its weapons.
The south-east Antrim 'brigade' has been in talks with General John de Chastelain and his Independent International Commission on Decommissioning since breaking away from the mainstream UDA last year.
General de Chastelain flew into Belfast for talks with representatives of both factions on Thursday. A source within the south-east Antrim group said a significant move on the arms issue had been made in the last few days.
The source said the commission and the NIO now recognised the faction as a separate entity from the mainstream UDA.
"We have made progress with the decommissioning body that has gone beyond talking," the source said.
"We will confirm that publicly when the process is concluded."
The source said the faction's members had backed the move.
The action of the breakaway group, which has links to the Beyond Conflict organisation led by Tommy Kirkham, will increase pressure on the mainstream UDA.
Continuing tensions between the two factions have led to clashes in recent months including a standoff in Carrickfergus, Co Antrim, in July that resulted in a police officer being shot in the back.
To date the mainstream UDA has ruled out any possibility of decommissioning. Earlier this month social development minister Margaret Ritchie removed £1.2 million of funding from the Conflict Transformation Initiative after the UDA failed to meet a decommissioning deadline.
The paramilitary group has said a "significant statement" on future intent will be read at Remembrance Sunday commemorations throughout Northern Ireland next month, although sources say that at this time members fiercely oppose any move on weapons.
The UDA's name change to the Ulster Defence Union will also be announced publicly on Remembrance Sunday.
At veteran loyalist Sammy Duddy's funeral last week a 'colour party' leading the cortege wore ties and armbands bearing the UDU crest – the first time the emblem has been used publicly.
A spokesperson for the south-east Antrim faction said it made the change to UDU 12 months ago.
"People realise there is a need for change and that problems with criminality need to be dealt with through the police and not with the paramilitaries as they would have been in the past," they said.
"We are moving forward with our programme of change independently."