The republican organisation said the Good Friday Agreement was a "significant development" and its full implementation would contribute towards the achievement of a lasting peace.

However, it said the go-between would be appointed after an assembly executive was set up and made no direct reference to weapons being handed over.

The IRA statement, made public on Wednesday, is seen as a crucial step in the process which could pave the way for devolved government and the election of an assembly executive.

It said: "We acknowledge the leadership given by Sinn Fein throughout this process.

"The IRA is willing to further enhance the peace process and consequently, following the establishment of the institutions agreed on Good Friday last year, the IRA leadership will appoint a representative to enter into discussions with General John De Chastelain and the IIC, (Independent International Commission on decomissioning)"

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The statement, is part of a carefully choreographed sequence of events, believed to have been laid down during the intense negotiations of Senator George Mitchell's review.

It is being published in this week's edition of An Phoblacht /Republican News.

Welcoming the statement, Sinn Fein chairman Mitchel McLaughlin said the IRA had shown "remarkable discipline, control and patience" in the 19 months since the signing of the Good Friday Agreement.

Senior Ulster Unionist Michael McGimpsey said the statement may convince his party that republicans are serious about decommissioning.

He said the way could now be open for the formation of an executive.

Michael McGimpsey: May fulfil twin objectives

"There is a possibity that we may be in business here. The business for us is achieving our party's twin objectives: Decommissioning and devolution, crudely put as 'no guns, no governnment.' It may be that this is another part of the equation for us to fulfil those twin objectives."

Northern Ireland Secretary Peter Mandelson described the statement as a "significant step forward."

But Peter Robinson, deputy leader of the Democratic Unionist Party, which is opposed to the Good Friday Agreement, said the statement was part of the plan worked out between the Ulster Unionists and Sinn Fein and did not have the promise of guns at a later date.

"All it is, is the willingness to appoint somebody to talk to General John de Chastelain after the institutions have been set up, without any commitment about how serious they will be in such talks, or whether they will deliver weapons at the end of the day," he said.

On Tuesday, Sinn Fein and the Ulster Unionists narrowed their differences on the critical issue of paramilitary weapons.

Republican shift

Sinn Fein President, Gerry Adams, stressed his party's support for the disposal of illegally-held weapons.

The written statement indicated a substantial shift within the republican movement, though it fell short of the actual surrender of guns and explosives to the international decommissioning commission sought by hardline unionists.