PRESIDENT Clinton is expected to make a significant intervention in the Northern Ireland peace process during his six hour visit to London on Thursday.
The US President is expected to discuss the issue with the British Prime Minister, Mr Blair, and to make a public appeal to the IRA for an immediate and unequivocal ceasefire. His remarks will be broadly in line with the speech by Mr Blair in Belfast earlier this month.
The key sticking point in talks between the British government and Sinn Fein is understood to be London's reluctance to take the current absence of IRA activity into account in assessing the republican movement's commitment to the democratic process.
The Northern Ireland Secretary, Dr Mowlam, referred to the issue in an interview on BBC Radio's Inside Ulster programme at the weekend.
Asked by the presenter, Jim Dougal, if she believed there was at the moment an unofficial IRA ceasefire, she replied that this seemed to be the case in Northern Ireland but it was difficult to know if it was also in operation in England.
Mr Dougal asked: "If there was a ceasefire announced, would you look at a period before it, when there had been no activity, as part of a testing period?"
Dr Mowlam said: "I think it would have to be taken into consideration, but I don't want to make a clear commitment that that time period would be important."
Asked how soon Sinn Fein would be in talks after a ceasefire was announced, she replied that it was "difficult to put a timescale on it."
She also implied that the reaction of the unionists to a ceasefire would be critical: "We have got to be sure that ceasefire has some meaning to the other participants in the Northern Ireland talks process."
Pressed on the issue of possible unionist reaction, she said: "We have to have a ceasefire that we can gee people to believe in. Now part of this is confidence building measures".
"So there is a lot of different parallel routes that we will be following and we must do our best to make sure that everybody can have some faith in the outcome."
She said that the absence of the Ulster Unionist Party in particular from the talks would weaken the process considerably.
"We want to do all we can to get and hold people in the talks process, but at the same time we have got to be clear that we have got to try and push this process forward, that we don't want anybody having a veto and holding it up," Dr Mowlam told the interviewer.
It is understood that the question of giving "credit" to the IRA for its inactivity may be discussed by Mr Clinton and Mr Blair this week. Asked if they felt Dr Mowlam had acknowledged that the Sinn Fein viewpoint on this issue was correct, republican sources commented: "She didn't quite say that."
Dr Mowlam's caution is being mirrored in republican circles: "We don't need exaggerated reports or tabloid headlines that cause everyone difficulties at this".
A second meeting between Sinn Fein and British civil servants is to be held shortly, and may take place this week. The Sinn Fein chief negotiator, Mr Martin MeGuinness MP, is expected to lead the party delegation to the unofficial peace conference in South Africa which begins on Thursday.
Republican sources said there had been "a marked change in mood" from the latter phase of Mr Major's government. However, on the republican side there was a wariness about past experiences with British governments that don't deliver."
A decision to call another ceasefire would be made when the IRA was convinced that there were going to be "real talks" with Sinn Fein taking part. However, events at Drumcree had the potential to "derail everything".
The key question for republicans was whether Mr Blair was prepared to learn from the mistakes of his Conservative predecessors.