Bertie Ahern warned UK Real IRA were attracting worrying number of 'the wrong people'

The revelation came in secret documents released as part of the State Papers.

The releases - which cover the years between 1991 and 1998 - revealed a remarkably friendly and open relationship between the British Labour Party leader and Taoiseach Bertie Ahern.

In 1997 and 1998, both men shared a level of personal contact via meetings, telephone briefings and exchanged memos never before seen between an Irish and British leader.

Mr Ahern made contact with Mr Blair in 1998 to brief him on the Real IRA amid concerns about their membership.

One telephone call which took place on July 31 1998, involved an exchange about the splinter Republican group, the Real IRA, just 16 days before the paramilitaries detonated a car bomb in Omagh, Co Tyrone which killed 29 people.

A further 220 people were injured in what became the single deadliest outrage of the Northern Ireland conflict.

Mr Ahern confirmed to Mr Blair that security officials in the Republic had been monitoring the Real IRA. He said gardaí believed the Real IRA membership comprised around 100 people.

The overwhelming majority were IRA volunteers who opposed the Good Friday Agreement and the Northern Ireland peace process - but included experienced veterans of major IRA campaigns.

"The quality of them I think are probably good enough in that they have an awful lot of the wrong people from our point of view. But they don't seem to be overly active," Mr Ahern told Mr Blair.

"Our security people, like yours, I think overstate the position. There are some of the key people who are hanging around but they are not doing an awful lot and the surveillance is showing that they are not.

"There is always the worry that somewhere along the way somebody slips you but I think our guy feels fairly happy that they know they're keeping a handle on it."

In the wake of the Omagh bombing, both leaders met in Belfast on August 16.

Mr Ahern told Mr Blair the Irish authorities were already looking at specific individuals.

"We were looking 100pc at McKevitt and (X) and the 32 County Sovereignty Movement and the Real IRA," he said.

Michael McKevitt had been the IRA's Quartermaster General but emerged as an opponent of the peace process. He was a key figure in the formation of the Real IRA.

McKevitt - who died on January 2 2021 aged 71 - was convicted before the Special Criminal Court in August 2003 of directing terrorism and of being a member of the Real IRA.

He was sentenced to 20 years and was released on Easter Sunday 2016.

However, McKevitt was never convicted of any specific involvement in the Omagh outrage.

"The dissidents were a dangerous and ruthless group with some support from former members of the Provisional IRA technical and engineering unit," Mr Ahern said.

The papers also reveal how Mr Ahern threatened to walk away from the Northern Ireland peace process and the fledgling Good Friday Agreement if key north-south bodies were reduced to meaninglessness to placate unionist demands.

In the two weeks leading up to the Good Friday Agreement deal, Mr Ahern warned Britain that unionists needed to understand and appreciate the scale of "the huge historical prize" they were about to secure from the deal.

"Let me be very frank. I am in an extremely difficult position," he said in briefing notes.

"Unionists are gaining a huge historical prize - the acceptance by nationalist Ireland, north and south, of the position of Northern Ireland within the UK."