CABINET Minister Jonathan Aitken was reprimanded by Government

colleagues last night after a serious weekend blunder undermined the

Prime Minister's authority.

Mr Aitken unwittingly encouraged nine Tory rebels to remain in exile,

just as Ulster Unionists are threatening to bring down the Government.

The crime of Treasury Chief Secretary Mr Aitken was to reopen in

public the Cabinet divisions on Europe. He trumped Mr Major's ace speech

last Friday night to Tory Euro sceptics. At Ministerial meetings

yesterday, Mr Aitken's blunder was the high point of discussions.

On Friday night, the Prime Minister offered yet another concession to

his Tory Euro rebels by indicating Britain would not only veto European

political and monetary integration but also put up new arguments against

a single currency. Chancellor Kenneth Clarke is scheduled to itemise

these later this week.

However, at the weekend Mr Aitken declared on TV: ''I don't want to

see a single currency -- period -- for as far as I can possible foresee.

I would hesitate for an eternity before I came out and said I would vote

for a single currency.''

This exploded a carefully contrived campaign by Mr Major to unite his

party. The Euro rebels were saying last night that the longer they stay

off the Whip, the more they achieve.

This hits Mr Major at the most delicate time in his negotiations with

Dublin on the future of Northern Ireland. Some of the nine rebels and

more Tory back benchers are severely cynical about his conduct of the

Irish negotiations.

Mr Aitken's blunder on Sunday morning breakfast TV was excused by

friends at the Commons last night as a slip of the tongue before the

cameras. He has apologised to Mr Major for this personally on the phone

yesterday -- but the damage had been done.

Shadow Foreign Secretary Robin Cook immediately demanded a General

Election on the grounds of what Mr Aitken said about the single currency

in Europe because, he claimed, the Cabinet is hopelessly divided on the

issue. Liberal Democrat leader Paddy Ashdown seeks next week in the

Commons to devise a motion on the European issue that he hopes will

bring the Tories down.

The Aitken blunder was being seized on as further evidence the Prime

Minister cannot control his Cabinet on both the European and Irish

issues at this critical time.

President of the Board of Trade, Mr Michael Heseltine, found it

necessary to tell the nation on Sunday -- after the Aitken intervention

-- that the European argument within the Tory party was getting out of

hand. He declared he would not ''pander to the whim of anti-European

public opinion''. The Government, he said, must dismiss the ''politics

of frustration and nostalgia'' and concentrate on winning the best deal

for Britain at the 1996 summit, even if concessions had to be made.

Behind the scenes at Westminster last night, a furious Mr Major was

privately fulminating about the Cabinet indiscipline. He was saying to

colleagues that if he is to be further undermined in this way, it makes

it difficult for him to keep the Irish peace process alive. Today, the

Prime Minister will discuss with Mr Clarke, how the European policy can

be put back on the tracks when the Chancellor spells out in some detail

future negotiating policy.

The internecine Cabinet dispute on the airwaves is damaging to Mr

Major not only in the preparations for European negotiations but, more

urgently, the life-or-death matter of producing a London-Dublin deal to

bring the Ulster Unionists together with Sinn Fein and the SDLP to start

negotiating a permanent peace solution.

Yesterday, Northern Ireland Secretary Sir Patrick Mayhew met Ulster

Orangemen to explain where the Government stands in talks with Dublin

following the furore caused by a leak concerning all-Ireland joint

institutions.

The Orangemen emerged from the meeting to say if such cross-border

institutions were left in the hands of a new Northern Ireland Assembly

they would be content. Spokesmen for the Loyalist paramilitaries

declared they too would be content.

Mr Dick Spring, Ireland's foreign minister, made clear yesterday his

government wants the framework document on the future of Northern

Ireland to be published by the end of this month.

Mr Spring, in Brussels for a meeting of foreign ministers, announced

he would meet Sir Patrick on February 14 for further negotiations.