AN extra layer of gloom settled on Government Buildings on Monday as news came through of the bombing of the British army headquarters in Northern Ireland.

There was never any doubt but chat the IRA was responsible. Last night's claim of responsibility only confirmed what Government sources were already saying Lisburn marked the end of the Provisionals' de-facto" ceasefire in Northern Ireland. The peace process was unravelling, but the implications of the new development were still unclear.

That the bomb was aimed at the British Conservative Party conference, which opened in Bournemouth yesterday, is beyond question. The action reflected traditional, physical force thinking within republicanism, which holds that a deal can be done with the British government over the heads of the unionist population in the North. It is an intrinsically anti-democratic approach and runs counter to the demands by Sinn Fein for substantive all party talks without preconditions.

The bomb did not come as a surprise to either government. Following the discovery of 10 tonnes of explosives in London in September, it was accepted that the IRA would attempt one of its "spectaculars". The only question was where.

The assessment from the United States was bleak. There was no real chance of an IRA ceasefire in advance of next month's presidential election. And, here at home, Gerry Adams and Martin McGuinness talked about the need for an entirely new talks process to facilitate a ceasefire. It sounded as if nothing would happen before next year's British and Irish general elections.

The two governments could not contemplate such a lengthy political vacuum. Two weeks ago, they agreed the terms of arms decommissioning arrangements designed to enable all parties to take part in the talks process. But these were rejected by the unionist parties. And David Trimble, of the Ulster Unionist Party, put forward his own proposals.

Since then, John Bruton and John Major have discussed the matter at Dublin Castle and have had two lengthy telephone conversations about the difficulties which have arisen. The upshot of those contacts is that the governments are holding the line on their decommissioning proposals and are seeking movement from the unionist parties and from republicans.

The talks process is the only show in town. Nothing will be done to change or modify it. And nothing will be done to jeopardise it. The Taoiseach emphasised this in the Dail yesterday. The governments would be very loath, in having got the talks started, to take an initiative which might have the result of stopping them."

Mr Major echoed the sentiments at Bournemouth with the words. "It would he irresponsible for us to walk away, having expended such time and effort in getting people around the table."

Dick Spring hoped that the people already at the table would accept their political responsibilities. He talked about the need for "meaningful negotiations across the table" and for an acceptance that the governments' decommissioning proposals represented the best way forward.

The only glimmer of hope was provided by the loyalist parties, which continued to urge restraint on the UDA and the UVF and spoke about the need for a political settlement which would embrace both communities.

While the loyalist ceasefire holds, there is some room for Government flexibility within the talks process, in spite of unionist resistance.

Little effort was made to disguise the official dismay felt in Dublin at the unwillingness of David Trimble to engage fully in the talks process. And the lack of progress made between the UUP and the SDLP in agreeing an agenda for substantive discussions was regarded as a sign of political weakness.

The reality of the situation is that the governments cannot admit that the multi party talks process is dead or dying. To do so would not only he an admission of failure, but an invitation to paramilitary groups to fill the vacuum with violence.

There must be a willingness by the parties to embrace compromise as John Bruton said if the talks are to survive and lead anywhere. At the moment, there is no evidence of such an appetite. But governments live in hope. And, while 11 of the 12 eligible parties remain at Stormont, they will work to complete the circle through the reinstatement of an IRA ceasefire.

In the meantime, attempts will be made to agree an agenda for substantive talks on issues arising from Strands One and Two. If that preliminary bridge could be built, it would open a road towards a Framework type solution and Sinn Fein would come under tremendous pressure to be part of any such political settlement.

The Taoiseach warned the Dail that nobody should expect instant or early solutions. People had been unable to agree on a form of government for this State for many years, he recalled, and just because agreement had not been secured in Northern Ireland since June 10th did not mean that the talks had failed.

Given the background of 25 years of violence followed over the summer by sectarian outrages, triumphalist marches and boycotts, it was going to be even more difficult to find a political solution in Northern Ireland.