Three of the four main dissident republican terror groups in Northern Ireland are to merge and reclaim the banner of the IRA, in an escalation of attempts to de-stabilise power sharing.

The Real IRA has been joined by Republican Action Against Drugs, which has been running a violent vigilante campaign in Derry, and a coalition of independent armed republican groups – leaving only the Continuity IRA outside the new group.

In a statement released to the Guardian, the new organisation claimed it had formed a “unified structure, under a single leadership”. It said the organisation would be “subservient to the constitution of the Irish Republican Army”.

This is the first time since the 1998 Good Friday Agreement that a majority of the forces of dissident republicanism has coalesced.