The court decided Mr McCombes was guilty of contempt

Alan McCombes was fined �500 when he appeared before Lady Smith at the Court of Session on Tuesday.

He was jailed last month for refusing to hand over an SSP document but released after three days when party officials presented it to the court.

The party will have to meet costs of about �45,000, it is understood.

BBC Scotland political correspondent Kit Fraser said the cost of the legal proceedings were thought to be a real burden for a party known already to be in financial difficulty.

The document at the centre of the wrangle contains minutes of the meeting at which Tommy Sheridan resigned as leader.

I think it's been an extraordinary situation Alan McCombes SSP co-founder

The News of the World believes they include details of Mr Sheridan's private life which would help in its defence of a defamation case brought by the former leader.

Speaking after the verdict, Mr McCombes said: "I think the penalties that have been imposed are extremely harsh.

"Not just the �500 but the tens of thousands of pounds of costs awarded against me, News International costs, the cost of raiding and searching my home and party headquarters in Glasgow and Edinburgh.

"I think it's been an extraordinary situation."

Financial appeal

SSP leader Colin Fox, who was in the Court of Session to hear the verdict, said party lawyers would discuss the costs in due course.

Mr McCombes said: "I certainly don't have any assets or resources and it may be a case that you have to get blood out of stone. I have to consider all the options."

A party spokesman said the debt was a personal one but the SSP would launch a financial appeal to raise the money.

Paul Cullen QC, acting on behalf of Mr McCombes, suggested to the judge the three days his client had spent in Saughton prison was adequate punishment for his actions.

'Sort of game'

Mr Cullen also opposed a motion by the defence to claim the costs involved in the search for the documents.

He argued that, if it had been clear to the party that the court intended to grant an order for a search of SSP offices, then details of where documents were not to be found may have been released.

Lady Smith described the party's apparent willingness to say where the documents were not, and not where they actually were, as "some sort of game".

She concluded: "I'm satisfied that it is appropriate that an order for expenses be pronounced against Mr McCombes in the terms sought.