As Mr McGuinness implied, the attempt to drive a wedge between London and Dublin could have ominous implications for the whole Irish peace process. The framework document is one crucial part of it, but it is also only one component of a complicated web involving the two governments, the Unionist parties, loyalist paramilitary groups, constitutional nationalists, Sinn Fein and the IRA.
The issues on the agenda include the maintenance of the IRA and loyalist ceasefires, the question of the terrorist armouries, the possibility of early release for the hundreds of imprisoned paramilitants, the introduction of Sinn Fein and extreme loyalists into the political processes, and the gradual demilitarisation and normalisation of life in Northern Ireland.
Other issues include the restructuring of the economy, policing reforms, and the construction of a political road designed to lead eventually to all-inclusive round-table talks dealing with Northern Ireland's future political structures and their relationship with Britain, the Republic and Europe.
The fact that the IRA ceasefire has held for five months has led to growing optimism that the peace will last. But the document always had the potential to cause such a crisis, in that its construction had to be subtle enough to keep both republicans andUnionists on the negotiating path. Its authors say they have been undermined by the Times report, which has wrenched out of context elements least palatable to Unionists and presented them in the worst possible light.
The two governments argue that the document, seen in the round, would be widely judged as balanced and fair to both communities in Northern Ireland. The hugely ambitious aim is to reassure Unionists that they are not to be railroaded into a united Ireland against their will, while at the same time convincing nationalists that their Irish identity will be fully recognised.
The document envisages a new Belfast assembly, a new north-south institution, and the modernisation of elderly British and Irish legal provisions concerning Northern Ireland. It was not quite finished, but its shape was clear.
John Major now faces the dilemma of whether or not to attempt substantial revision of the almost-completed text in response to yesterday's Unionist anger. He will be anxious not to lose the goodwill of the Ulster Unionist Party, whose support could be crucial in close Commons votes.
The more hard-line MPs such as John Taylor are already warning that proceeding with the document along the intended lines will sunder the Unionist-Conservative relationship, thus severely weakening the Government's chances of survival. The party leader, James Molyneaux, has been more ambiguous and enigmatic, but clearly wants wholesale changes.
On the nationalist side, any attempt at substantial renegotiation would cause an outcry, since the Government would be seen as responding to threats of a loss of parliamentary support.
Nationalists in general and republicans in particular frequently complain that Mr Major pays undue attention to the Unionists because of their strategic position at Westminster.
Opting for renegotiation would plunge Anglo-Irish relations into a new era of bitterness, sending reverberations through the entire peace process. Ignoring Unionist opinion, on the other hand, would also damage the inclusive nature of the process, as well as placing his administration in peril.
The leak and its repercussions have thus, at a stroke, created a crisis which threatens both the Government's survival and the prospects for peace.
James Molyneaux: "People in Northern Ireland have already made up their minds, and don't like what they see"
David Trimble: "If the Government endorse this, there is no question of being able to maintain any relationship."
Ian Paisley: "You can't expect any self-respecting Unionist to sit down at a table if that is going to be on the agenda."
John Hume: "At this very sensitive period speculation is not only wrong, it's utterly irresponsible. Let us stop."
John Bruton: "It's not our intention to impose a document in any way without ample opportunities for agreement."