David Trimble is showing no signs of jet lag after a Washington trip which has left some in his party back home feeling pretty shattered. Maybe it's just the early morning sunshine bathing his Commons room - an intimation of summer and lazy days to come in the Tuscan hills. But one fancies it's more to do with having just been on BBC Radio Four denouncing BBC Northern Ireland for its "misrepresentation" of what took place last Friday.
Given his complaint about the media coverage, what significance does he think should be attached to his stated willingness to consider "a fresh sequence" which would put Sinn Fein back in government without IRA arms up-front?
The significance, he says, is that, despite the fact that the republicans let them down, Ulster Unionists are prepared to have another go. "But this time it's got to work. We were prepared to move in November on the basis of an expectation, and a calculation, of what we thought they might do. This time we can't do it unless we're sure it's going to work."
Obviously he is thinking in terms of decommissioning following devolution, and is looking to republicans for the assurance that it will. But, significantly, he adds: "I will not prescribe in advance what creating certainty means because that would be problematic. The only people who can provide the certainty are republicans, and I want to see what they are prepared to say and do."
In terms of the broad political picture then - given that explanation - does Mr Trimble think anything much has changed? "In substance, no" he says and then adds: "The only way in which I'm looking at that is . . . I'm not being prescriptive as to what creates certainty and I'm leaving that for republicans to address."
Is he indicating that he might accept a formula on weapons which is not time specific? "I think that would be very, very difficult to persuade the party to look at, and I think that sort of formula I doubt would carry credibility at all," comes the reply.
"The underlying question is the simple question of whether these people are going to turn their backs permanently on terrorism. If they are, then all these difficulties they've created about the issue shouldn't be a problem. And you've got to say: `Well then, apart from the logistics, and apart from prudence in terms of not provoking too big a reaction from dissidents, what's the problem?' "
Might the right sort of language render decommissioning less of a requirement for the Ulster Unionist leader? He says not. "No. I think at the end of the day the weapons have to be dealt with. If you're committed to peaceful means then you don't want weapons, or to keep weapons, because one knows that weapons don't just rust and will eventually get into the wrong hands." The only argument for not proceeding immediately "is the need to manage the situation and to ensure you don't provoke too big a reaction from dissidents".
Mr Trimble resists the suggestion that he is attempting to help Mr Gerry Adams and Mr Martin McGuinness "manage" their problem. "No. I'm just giving them space and time and opportunity. I'm not going further than that."
Ken Maginnis says only affirmative answers to the famous Mallon questions - "Does the IRA intend to disarm, and, if so, when?" - can provide the basis for Sinn Fein's re-entry to the executive. Mr Trimble confirms he is "in the same ballpark basically, because we're saying it's answers from Sinn Fein".
But does he agree with Mr Maginnis that answers to the Mallon questions should be followed with a clearly defined schedule for decommissioning?
"Well, why shouldn't it be?" he demands. "The first of Mallon's questions is `Are you going to do it?' If there's a positive answer to that, then it's perfectly natural to expect people to explain how they're going to do it, and so on and so forth."
That's "all out there" declares Mr Trimble. "But look, there isn't any point in getting bogged down in a detailed . . . other than to state the general requirement of giving positive answers to these questions . . . there's no point getting down into the detail."
But isn't that precisely why so many people in his party are nervous about what Mr Trimble signalled in Washington? The reply is a little tart: "No it's not, actually. I find very little nervousness now that I've come back. There are the usual people who are opposed to this entire process and seize every opportunity to criticise. Those committed to the process quite understand what I've said."
On one point of detail: Mr Trimble presumably accepts the political reality that decommissioning will not be accomplished by May 22nd?
He most emphatically does not. "There's no such reality. I recall the comment, not made to me but to a member of the government by Mr Martin McGuinness, that once they've decided to do it they can do it in half an hour." There may have been an element of boasting, Mr Trimble ventures, but he doesn't doubt the underlying truth of it.
The UUP leader foresees "a serious credibility problem" opening up if the May 22nd date is not met, and says this is part of the reason he said what he did in Washington. People are wrong to think they can "play it long" he insists, in obvious reference to Sinn Fein.
And to those in his own party who think it's time to get off the decommissioning hook? The suspended First Minister says the problem is for the paramilitaries to resolve. "We cannot allow terrorists in government and say `You can retain the means and capacity, and we know you can go back to terrorism whenever you like.' You can't have that."
Despite his disappointment last time, Mr Trimble holds firm to the belief that the republican political project will not prosper in Northern Ireland or the Republic "until they get rid of the whiff of sulphur" - that it is "in their own political interest to do this, as well as being in the interest of society as a whole".
For all the tough talk, of course, Mr Trimble's critics suggest he will never be prepared to walk away from the Good Friday accord, and will do whatever is required to save it.
He's not having that: "Ah, but that's only to save the agreement we made, not to save something else . . ." Nor is he having the suggestion that London and Dublin are hoping for greater flexibility from him after this Saturday's meeting of the Ulster Unionist Council. With a mixture of anger and disdain, Mr Trimble says emphatically: "I dislike intensely the suggestion that I'm going to do one thing this week and do something different next week. Again, that is part of the reason why I said what I did on Friday - a week ahead of the party meeting. As I say, I dislike intensely the suggestion that one would behave in such a dishonest manner."
Looking ahead to Saturday, the thought occurs that he might think it better for the health of his party if one of the MPs who have consistently opposed him directly challenged him for the leadership. Mr Trimble coolly replies that the party's health would be better served if people accepted the democratic decisions made by it. He makes the point that he has consulted the party "more fully and more extensively than any of my predecessors", which he thinks is part of the reason why the party has stuck with him. "But I think one is entitled to say `You should accept the democratic decision'. I'm quite sure what that decision would be if it were put to the party on Saturday."
Of Saturday's other "challenge" - the bid to tie re-entry to the executive with a British commitment to retain the RUC's royal title - Mr Trimble says he shares the objective but thinks the tactic "ill-advised".
With his own tactics for the emergency UUC meeting still undecided, Mr Trimble interestingly does not share Mr Maginnis's view that the passage of Mr David Burnside's motion would make the UUP "a single issue party" or immobilise the entire political process.
"I think we want to keep the language on this issue, and on all issues, reasonably proportionate. It wouldn't have that effect but I still think it would be ill-advised."
Beyond insisting that he "would expect John Taylor to be standing with me" (and that his deputy leader remains "very valuable" to him), Mr Trimble resists all invitations to say how he will play the RUC debate on Saturday.
But he is clear on one thing. Asked if there would be implications for his leadership should the motion be carried against his wishes, he replies: "No . . . I decide what has implications for my leadership."
And as he heads off to Heathrow it seems pretty clear that Mr Trimble does not anticipate being relieved of that duty just yet.