Dr Mo Mowlam is blocking a renewed effort to have the right to membership of the British Labour Party extended to people in Northern Ireland, so putting herself on a potential collision course with the Prime Minister, Mr Tony Blair.
Labour and unionist sources claim Mr Blair privately accepts "in principle" that Labour should end an anomaly whereby Irish citizens living in Dublin can join the party while British citizens living in Derry can not.
The end of the ban on Northern Ireland members would be a landmark victory for "equal citizenship" campaigners who have long argued that citizens should have the right to vote for a party capable of forming the government of the state to which they belong and would almost certainly be regarded as a welcome "confidence-building measure" within the unionist community in the North.
Moves to extend Labour's organisation to Northern Ireland have previously been resisted on the grounds of the party's support for Irish unity by consent, and Labour's formal ties with the SDLP, its "sister party" in the Socialist International.
However, those campaigning for change have been increasingly confident that these obstacles and objections would be overcome since the Belfast Agreement was concluded on Good Friday.
A number of Labour MPs, including the Belfast-born Ms Kate Hoey, who was promoted to the Home Office during the recent reshuffle, pressed the issue with Mr Blair during the referendum campaign last May. Ms Hoey, and fellow MPs Mr Harry Barnes, Mr Mike Connarty, Mr Alan Johnson and Ms Shona McIsaac subsequently wrote an open letter to Mr Blair in the Daily Telegraph suggesting that the end of exclusion (of Northern Ireland people) would help renew the North's political culture and build Mr Blair's "non-sectarian vision" for the future.
The Irish Times has learned that at a meeting of the Ulster Unionist Parliamentary Party on Friday, July 10th, Mr David Trimble surprised his colleagues by raising the likelihood of Labour organising in the North as a welcome contribution to the development of more "normal" politics there. And the issue dominated a meeting of the Parliamentary Labour Party, attended by Dr Mowlam at Westminster two weeks ago.
However, the terms of a letter circulated to Labour MPs by Dr Mowlam would suggest that the leadership's attitude to organising in the North, or opening its doors to people resident there, is unchanged.
The "model" letter was sent out by Dr Mowlam's office on June 30th, suggesting how Labour MPs might respond to correspondence from people in Northern Ireland regarding Labour Party membership.
Dr Mowlam's letter, which The Irish Times has seen, says: "Labour's position, as established by the party constitution, is that we do not recruit members in Northern Ireland, nor do we stand candidates for election in Northern Ireland. This position has been supported by a majority of Labour members for many years."
Dr Mowlam's draft speaks of the "real change happening in Northern Ireland as a result of the Good Friday agreement". It continues: "These developments have come from within Northern Ireland. They have come from agreement among the parties and the votes of the people. Labour's view is that any moves towards establishing new political organisations should also come from within Northern Ireland. We do not believe that inviting members to join Labour or standing candidates for election would make a helpful contribution to the welcome developments we are now seeing in Northern Ireland."