A statement from the group said: “While ONH accept that the right of the Irish people to use armed disciplined force to end the violation of Irish national sovereignty is unquestionable, our review has concluded that, at this time, the environment is not conducive to armed conflict.
“Therefore the leadership of ONH are announcing that with immediate effect we will suspend all armed actions against the British state.”
The statement was read by veteran trade unionist Peter Bunting, who was part of a delegation that met with ONH members over the past two years.
The announcement comes on the eve of a new talks process aimed at saving the devolved institutions at Stormont.
ONH has been behind some of the most high profile terror attacks in Northern Ireland including the attempted murder of Catholic policeman Peadar Heffron in January 2010.
Mr Heffron, a fluent Irish speaker and prominent Gaelic footballer, lost a leg and uses a wheelchair as a result of the bomb which was detonated as he drove to work from Randalstown, County Antrim.
Despite comprising around just 50 members, Oglaigh na hEireann, which roughly translates as soldiers of Ireland, was among the most active and deadly dissident groups opposed to the peace process.
Its membership includes a number of former senior figures from the Provisional IRA including so-called “big names” from Belfast, Londonderry, South Armagh and north Louth in the Irish Republic.
Other audacious attacks included an attack on the Northern Ireland headquarters of MI5 at Palace Barracks in Holywood, County Down. Although there were no serious injuries, damage was caused to nearby houses when the car bomb exploded as the area was being evacuated.
ONH was also responsible for an attempt to bomb a police station in Londonderry, the targeting of a British Army major in County Down and a bid to shoot down a Police Service of Northern Ireland helicopter in South Armagh.
The group was believed to have gathered information on Catholic police recruit Constable Ronan Kerr, who was killed outside his home in Omagh, County Tyrone, in March 2011.
More recently, ONH has been blamed for punishment-style shootings targeting alleged drug dealers in Belfast and Londonderry.
The decision to turn away from violence was not made quickly.
Last Easter, the group signalled that the group was ready to abandon violence.
The statement issued today concluded: “The leadership and volunteers of ONH remain unbowed and unbroken.
“We will continue to protect our membership and base, as we move forward in a spirit of unity and determination to achieve our political goals.”
Accompanying Mr Bunting at a press conference in Belfast was Fianna Fail TD Eamon O Cuiv and Londonderry community development worker Conal McFeely.
Mr O Cuiv, who has visited republican prisoners in jails on both sides of the border, said he was “confident” the ceasefire would stick.
He said: “Normally when republicans say the guns are silent, they stay silent.”
The decommissioning of weapons did not form part of the discussions that led up to the announcement.
The PSNI Assistant Chief Constable Stephen Martin said the declaration indicated that some violent dissident republicans were starting to recognise that violence was not a bargaining chip for peace.
He also appealed for other armed groups to follow suit.
Mr Martin said: “Our communities do not want to live in fear of violence and my challenge to ONH is to meet people’s expectations and cease using violence immediately. This includes all types of organised criminality within communities.
“The group has announced it is to suspend all actions against the ‘British State’, however, for years now, members have been heavily involved in extreme violence against people living in their own communities, including carrying out brutal beatings and shootings, as well as menacing acts of intimidation to create fear and control.
“These vicious attacks must also be consigned to the past. It will be deeds that count ultimately, not words.”