THE TAOISEACH, Mr Bruton, is understood to have asked the SDLP to help ease Mr John Major's difficulties by abstaining in last Monday night's crucial House of Commons vote on the Scott report.
The Irish Times has been told that Mr Bruton's unsuccessful intervention came during a lengthy telephone conversation with the SDLP leader, Mr John Hume, just hours before the cliff-hanging division on the Arms for Iraq affair.
News of Mr Bruton's direct involvement in the issue is certain to cause controversy at Westminster and acute embarrassment in Dublin.
Mr Hume last night refused to "confirm or deny" anything about his conversation with Mr Bruton, which is thought to have taken place at about 7 p.m. last Monday.
The SDLP leader said: "There's no way I'm going to discuss a private call with the Taoiseach, even if he only rang to say it was Monday night. And I'm not confirming or denying anything about the call."
A Government spokesman confirmed that a conversation had taken place between Mr Bruton and Mr Hume on Monday, but said that he knew "nothing of the immediate circumstances".
Attempts by Dublin officials to obtain a response from the Taoiseach's party in Bangkok to Irish Times inquiries apparently failed over a seven-hour period.a However, the nature of Monday's night's conversation between Mr Bruton and Mr Hume has been the subject of rumour and speculation at Westminster over the past few days.
Sources in London, Belfast and Dublin last night expressed surprise that the Taoiseach could have personally intervened in the affairs of the House of Commons.
One senior Irish source said that he thought the Tanaiste, Mr Spring, knew nothing about such a call and would almost certainly have counselled against it had he been consulted. But another confirmed his knowledge of the call while discounting suggestions that the Taoiseach might have been acting at the request of Mr Major.
Other sources said yesterday that they knew about the call, believed to have been initiated by Mr Bruton, while disclaiming detailed knowledge of its content.
One MP said: "I know a phone call was made and the vote was discussed. I was informed of that." Another said: "I have heard the rumours. I heard it on Monday night, but not before the die was cast. I think there's some validity, all right, but I don't know the detail."
SDLP sources made it clear that there had never been any question of their not opposing Mr Major's government in Monday's vote.
One SDLP source said yesterday that he had never known a Taoiseach or an Irish minister previously approach the party about how it would vote on an issue in the House of Commons: "I find it totally, absolutely extraordinary, unless the British government were really desperate."
One benign view last night was that Mr Bruton's action reflected the depth of his concern about the attempts by both governments to revive the peace process and his anxiety that Mr Major's room for manoeuvre in the Anglo-Irish negotiations should not be restricted by his dependence on unionist votes in the Commons.
But the news gave a dramatic new twist to the ongoing row as to precisely what happened between the Ulster Unionists and Mr Major's government in the hours before Monday night's vote.
A potential rebel Tory MP, Mr John Marshall, said that he had finally been persuaded to back the government because he believed Mr Major was being "blackmailed" by Ulster Unionists "holding a pistol to his head".
Mr Marshall said that he responded to an eleventh-hour appeal from Mr Major because, if the Ulster Unionists had succeeded in their attempts, the "peace process would have been kyboshed".
Downing Street refused to comment yesterday on Mr Marshall's claims. But the Labour Chief Whip, Mr Donald Dewar, said that doubt had been cast on Mr Major's earlier claim that no deals had been offered and this would require further explanation from the Prime Minister on his return from Bangkok.