THE Tory Party's General Election campaign in Scotland was dealt a devastating blow last night when MP Allan Stewart resigned from the country's safest Tory seat.

He cited recent press reports on his health and personal life which had caused ''great family distress and personal strain'' as his reason for standing down from the Eastwood constituency near Glasgow, where he had an 11,688 majority in 1992.

Local party officials insisted that no pressure had been put on him to resign, despite the tabloid newspaper articles which alleged that he had received medical treatment and had been involved in a secret friendship with a woman other than his wife.

They admitted that Mr Stewart's health had suffered under the pressure of the media coverage, but made it clear they felt this week's claims about his personal life were ''unsubstantiated''.

The Eastwood officials did say, in their statement an-nouncing his resignation, that the MP's judgment had been suspect, but stressed that this related only to the incident in 1995, when he was forced to resign from the Scottish Office after being fined for a pick-axe confrontation with anti-motorway protesters on the site of the M77, then under construction in his constituency.

They will meet later this week to pick a successor to Mr Stewart, 54. Details of his medical condition were being kept confidential, but one official said he was ''not looking good''.

Reaction to Mr Stewart's resignation came from all sides of the political spectrum last night.

SNP leader Alex Salmond said: ''I am very saddened to hear of this decision by Allan Stewart. He is a hard-working and respected constituency MP with friends on all sides of the House of Commons.

''He is the most popular Tory MP in Scotland and I do not believe his constituents would have let the tabloid stories about his personal life affect their vote. He has made a very difficult decision and people of all political views will wish him well as he rebuilds his life.''

Mr Brian Wilson, Labour campaign spokesman, said: ''On a purely personal level, I am very sorry that this has happened. Allan Stewart has always been straightforward to deal with and to argue with. Labour has an excellent candidate in Eastwood and Allan Stewart's decision to stand down transforms the outlook in this seat.''

Mr Jim Murphy, the Labour candidate in Eastwood, said: ''At this time, my sympathies are with his family. He has worked hard and has been a worthy opponent. He has a very strong personal following and with any new candidate I look forward to a campaign on the ideas between New Labour and the tired Tories.''

A statement issued on behalf of Scottish Secretary Michael Forsyth last night read: "Allan has been an outstanding Conservative MP and was very popular in the House of Commons and he will be sorely missed. He never lost an opportunity to display his blue rose of Eastwood and spoke up for his constituency.

There was speculation last night that Mr Forsyth might move from Stirling to Eastwood, but this was dismissed by a senior party offical as ''preposterous''.

Friends and senior party colleagues of Mr Forsyth felt it was not in his nature to do anything which smacked of cutting and running from the wafer-thin majority in his own Stirling constituency.

With party morale north of the Border reeling under the Eastwood body blow at the outset of the campaign, the feeling was that such a move would send out terrible signals to others contesting marginal seats.

Mr Forsyth is understood to have told close colleagues that he had no intention of seeking a move to Eastwood and would stay and fight his corner in Stirling. One senior source told The Herald: ''Seat-hopping has an unfortunate history and I think this is extremely unnecessary.

''It would look too much like running away and would be bound to undermine other candidates in marginal constituencies. It would be bound to have a bad effect on morale if he was seen to cut and run.

''This just isn't in Michael's nature. He would have to be put under an enormous amount of pressure to even consider it.''

The inside speculation last night was that the prime candidate was party vice-chairman Jackson Carlaw, who has received widespread plaudits for masterminding the ''tartanisation'' of the Scottish Tories over the last year, but it is understood family pressures may count against him going to Westminster. He in turn, ruled out that possibility last night.

The other obvious candidate of sufficient calibre would be party chairman Sir Michael Hirst, who has parliamentary experience from his days as MP for Strathkelvin and Bearsden, but the obvious drawback there is that he has been widely tipped for elevation to the Lords.

Mr Stewart's dramatic decision to quit following a meeting with constituency party officials was described by his local chairman as ''a human tragedy of immense pro- portions'', but with the elec- tion looming in barely a month the party has to move quickly.

Last night Conservative Central Office was insisting the party structure meant it was entirely a matter for the constituency. Equally, in an organisation where loyalty is prized above all, local officials could be expected to do whatever was best for the party nationally.

There lies the tactical rub. What would be more beneficial in the long run for Scottish Tories - keeping up short-term morale in seats they may lose anyway when Mr Forsyth may well lose too? Or swallowing collective pride for the sake of ensuring that their most potent weapon is still in use in the next Parliament.

Labour can expect a torrid time getting their devolution Bill through Westminster in any case, but with Mr Forsyth still there to harry away at them it would be harder still.

It would also entirely skew Labour's election planning in Scotland, which is heavily built around the effort to unseat Mr Forsyth in Stirling.

As one source put it last night, it would be disastrous if the impression was given that Mr Forsyth was leaping at the chance of a safe seat. But if he moved under pressure, for the sake of the greater good of the party as a whole, perhaps under the guise of a joint approach from the two constituencies, then it might be a different matter.

Either way, the Tories have to act quickly, pick their candidate, put this early blow to morale behind them, and get their campaign up and running.

Dear Ian,

Recent press reports on my health and personal life have caused great family distress and personal strain. After discussing my health and position with Susie, who has always been so supportive of my role as the Member of Parliament for Eastwood, I have decided to resign as Prospective Parliamentary Candidate.

I do so with great regret so near to a General Election but I am sure that the Association will be able to select an excellent candidate and achieve a resounding majority.

I would like to express my deepest thanks to you and all the Officebearers and members down the years for their personal loyality, fortitude and hard work on my behalf through four successful general elections. It has been a unique privilege to have served to the best of my ability the people of this marvellous constituency.

I am now taking a break. The Association will of course have my full support as an ordinary member.

Yours ever, Allan

Allan Stewart's letter of resignation to Mr Ian Muir, Chairman of Eastwood Conservative Association.