JOHN Swinney will try to shore up his battered leadership this week ahead of a crucial meeting of the SNP's national council, which decides the party's election strategy.

If he fails to carry the day in Stirling on Saturday and then tries to cling on regardless, he is expected to face a stalking horse candidate this autumn.

Despite insisting, in the wake of last week's poor European election results, that he would remain leader until at least 2007, the odds on Mr Swinney's survival lengthened yet again yesterday after a fresh call for him to quit, and a reported lack of support among MSPs and the party rank-and-file.

Jim Sillars, former deputy leader of the SNP, added his voice to those clamouring for Mr Swinney to go, saying he feared a disaster at the general election if he stayed.

Mr Swinney's problems deepened when Adam Ingram, Nationalist MSP, said: ''A change in leader may or may not be necessary.'' At the inaugural meeting of the Beith 1320 Independence Speakers Club, Mr Ingram said the party should change its strategy to focus on independence.

He added: ''We need a change of strategy and direction and should not be focusing on personalities. A change in leader may or may not be necessary. But it will not be sufficient to turn round the party's fortunes.''

Surveys of SNP branches and MSPs by the Sunday press also showed large numbers wanting Mr Swinney to step aside after he led the party to its third electoral reverse since 2000. Another report said Mr Swinney was about to receive a visit from SNP grandees - the mythic ''men in grey kilts'' - telling him he must go for the

party's sake. The ill-omens mean this week will be crucial for Mr Swinney.

The quarterly national council meeting will bring him face to face with senior activists, in the first major sounding board of grassroots opinion since the SNP saved its two MEPs in the European elections, but almost slipped into third place behind the Tories on share of the vote.

Several senior SNP sources said Mr Swinney was in for a jolt when he realised the depth of the party's depression.

Although Mr Swinney said last week that he would stand in the annual leadership contest this September, activist discontent would almost certainly flush out a stalking-horse candidate to run against him, despite the damage to the party's image.

One source said Mr Swinney had no chance of again securing the 84% of votes which let him see off a challenge by a little known Bill Wilson last year, as abstentions ''would go through the roof''. With a poor win as good as a defeat, Mr Swinney would then be forced into a humiliating exit.

Nicola Sturgeon, the loyal shadow justice minister, is the favourite to succeed her leader.

Mr Sillars's call for Mr Swinney to resign followed one last week by Gil Paterson, a former MSP and member of the SNP's ruling national executive committee.

Michael Russell, the former SNP chief executive, also put more pressure on Mr Swinney yesterday, writing in an open letter to him: ''(You) deserve some private space to decide on your immediate future.''

A survey of 24 of the SNP's 26 MSPs in one Sunday paper found 11 wanting him to quit, nine supporting him, and four who refused to comment. A poll of 41 branch conveners in another paper found only 22 backing Mr Swinney, and 11 of those thought he should go after the general election.

However, Kenny Gibson, the ex-list MSP for Glasgow, told the BBC some in the party had never given Mr Swinney a chance, and if there had been electoral failure ''then the SNP failed collectively. It did not fail because of one man''.

He added: ''The people who are trying to undermine John Swinney should stop moaning and groaning. They should either support John or in my view they should simply go and join another political party because they are certainly not advancing the independence cause.''

A spokesman for Mr Swinney dismissed the reports as froth. ''If the party does not want John any more, then they have a way to say that. But he believes they want him to stay.''