As the tempo of political activity in Northern Ireland increases, so too does the frequency of violent incidents. There have been three sectarian killings in two days, posing an enormous challenge both to the security forces and the politicians.

Violent groups on both sides seem determined to wreck the possibility of progress at Stormont at the very moment negotiations have received a fresh injection of energy.

The pan-nationalist front between Dublin, the SDLP and Sinn Fein suffered a seismic shock last week with the publication of the Propositions on Heads of Agreement prepared by the two governments.

Some critics of the paper have expressed surprise that something so short could have taken so much time and effort.

The Taoiseach was meant to be enjoying a winter break in the Malaga region of Spain, but found himself making about a dozen calls a day in his efforts to tie up a deal. British sources say transcripts of the calls between the two prime minister are a far bulkier item than was the case when Mr Major and Mr Bruton were in office; this may reflect the health of the peace process more than the state of relations between the two former government leaders.

Other observers, particularly on the British side, are said to be surprised that, given the length of time absorbed and the quantity of sweat spilt, Sinn Fein was not brought "on board" by Dublin, which is meant to have a "special relationship" with the party. But, since the problem was seen as one of getting the unionists completely engaged in the process, Sinn Fein was never going to be fully satisfied with what emerged.

Early Sinn Fein reaction was negative and became more so during the week as anger grew among their followers over an apparent sell-out by Dublin. Voices appealing for a calmer and perhaps more rational assessment of the document were ignored amid a climate that was heavily influenced by the continuing sectarian killings and the feeling that any Catholic anywhere in Northern Ireland was a potential target.

However, Dublin has mounted what one insider called a "rescue mission", with the aim of reassuring Sinn Fein that it has not been sold down the river. Government sources point out repeatedly that the Propositions are only a basis for discussion and that Dublin also envisages the establishment of a free-standing North-South body with executive powers.

At a private tete-atete (some have called it a "crisis meeting") with Mr Ahern last Friday, Mr Gerry Adams raised his concerns about the Propositions document, particularly the fact that the Northern Ireland assembly was presented as something of a fait accompli, and the North-South dimension was weaker and less specific than in the Joint Framework Documents.

It is understood that the Taoiseach was very attentive to the Sinn Fein leader as Mr Adams outlined in unequivocal terms the difficulties created by the new document.

The largely-unspoken subtext in the present situation is the likely response of the IRA to the trend of events. The organisation is seen by its supporters as a defender of the nationalist community against the type of onslaught currently being mounted by the Loyalist Volunteer Force, and the latest killings must increase pressure on the IRA to break its ceasefire.

It is also probably a fair deduction that the IRA did not call a ceasefire to achieve a Northern assembly with emasculated North-South bodies. Observers have noted an increase in traditional anti-partitionist rhetoric from Sinn Fein, possibly reflecting pressure from the nascent 32County Sovereignty Committee.

The SDLP has mounted a strong defence of the approach taken by the two governments, arguing that there is nothing in the Propositions paper which was not signalled in the Framework Documents of 1995 and that nothing of substance in the Framework Documents has been left out of the Propositions paper.

THE old hostility between Sinn Fein and the SDLP, which was such a prominent feature of the Westminster elections, now appears to be surfacing again. One observer commented that the pan-nationalist front was self-destructing.

In that situation one might expect suppressed glee on the other side of the house, but Mr John McCrea, secretary of the Grand Orange Lodge of Ireland, has described the NorthSouth ministerial council as a "dangerous" proposition.

The Rev Ian Paisley said that the proposal to repeal Section 75 of the Government of Ireland Act of 1920 was the most damaging aspect of the proposals. "This is the title deeds of the Union", he said.

Meanwhile, Mr David Trimble has put a question mark over the notion of himself as prime minister in a new Northern Ireland administration. Speaking at Westminster, he told the Sunday Telegraph: "That's something I am going to have to think hard about, because the real seat of power is here."