The British Prime Minister, Mr Tony Blair, has said that President Clinton has "given a very clear signal and understanding that he would be delighted to come back to Northern Ireland if the peace process goes according to plan".
The obvious time is May when Mr Clinton will be in Britain for the G8 economic summit. The peace negotiations deadline is also May but without any date mentioned.
Does this really allow President Clinton to go to Northern Ireland in May?
The Irish Ambassador to the US, Mr Sean O hUiginn, is well placed to assess this. Asked if the President could only come if the peace negotiations were concluded, he said: "I don't think he would come into a chaotic, unstructured situation. The first thing the White House would do would be to look at the context in which he was coming, that it was a positive one.
"The ideal would be that this would be a done deal and a handshake and that the President would be associated with that. If that were to occur, the motivation for the President to come would be very strong indeed, but it would probably be going too far to say he could never go in any other circumstances."
But even if the negotiations were over, would President Clinton want to visit Northern Ireland in the middle of the subsequent referendum campaign?
Mr O hUiginn said: "It's purely hypothetical, but you could imagine a stage where an agreement had been done, had a glow of general consent/consensus about it and had not yet gone to referendum. There could be contexts where the President's involvement could not in any sense be controversial."
On how the US is playing a role in the peace process, he said there were different levels.
One way is "by making the weather, as it were, for a climate of agreement where a lot has been done, some of it in public in terms of access to the White House, some of it behind the scenes".
This could be very important psychologically. For example, in what has been a "very inward situation", the fact that unionists and others can come to the White House "helps to broaden the perspective in a very real, psychological way".
Much could also be done behind the scenes. "The US is the most powerful country in the world and a friend to all sides which can, in a very private way, indicate that it inclines towards one or other option in a situation. But that would never be done in a way that boxes people into a corner. That would not be productive."
He said "an up-front, hands-on" involvement in the peace negotiations would be risky for the US and would "not be the most effective use of American influence".
"I would be surprised if at any point you would get the US coming in and saying in relation to some specific proposal: `You must take option C'. I think it will never be that micro-managed."
The Minister of State, Ms Liz O'Donnell, a member of the Government's negotiating team who spent a day last week in meetings in Washington with the administration and Congress, said she was "very impressed by the US hands-on, daily interest in minutiae".
The US had a unique role to play and it was "very reassuring for us that President Clinton is willing to help".
However, she said the whole point of the negotiations was "to get the parties to take responsibility themselves for the overall agreement, rather than an outside person or even the two governments imposing anything".
"The whole thrust of our objective is to get people to have a stake in the final outcome so that then they can take responsibility for that and sell it to their constituency."