Scotland's First Minister Alex Salmond has defended his decision not to contact police over claims his bank account was hacked by The Observer in 1999 and declined to name the source of his information.
A spokesman for the First Minister said Salmond believed it was up to the newspaper to investigate the issue – claiming that if he reported the matter to police it could result in the disclosure of his source.
"What is necessary is that the newspaper looks more deeply into this," he said.
Asked why Salmond had not contacted the police over The Observer issue, the spokesman added: "His current view is that it's the responsibility of the newspaper to properly investigate this and to accept that they were engaged in such activities.'
He later added: "The first minister's not ruling out any option for the future".
Asked if his source was former Observer columnist Alex Bell, now head of policy, research and strategy in Salmond's team of special advisers, the spokesman replied: 'I have nothing to add to the remarks that the first minister made yesterday, which is that the information was provided to him by a former Observer journalist, and he will respect the confidentiality of that source."
Salmond told the Leveson Inquiry on Wednesday that he was informed by a former Observer journalist that the newspaper gained access to his bank account in 1999.
At that time, the SNP leader was an MP seeking to win a seat at Holyrood in the first Scottish Parliament election. No story was published by the Observer relating to the hacking claim.
Salmond's spokesman also questioned whether there was a connection between the allegation and an unpublished and "baseless" story that the first minister, a horse racing fan, had gambling debts.
The spokesman also referred to Operation Motorman, a 2003 investigation by the UK Information Commissioner into alleged breaches of data protection law which found The Observer had used the services of an investigation agency on 103 occasions.
He later recalled getting calls from journalists in the run-up to the 1999 election 'about a story that was going round that the first minister had gambling debts, which may very well be connected to this particular issue that the first minister talked about yesterday, which was always a total and utter fiction,'he said.
He added: "Many Scottish journalists were seeking to write a story about something that was simply untrue, totally baseless.
Salmond wrote to the editor of The Observer, John Mulholland, last July saying: "It has been brought to my attention that there was a strong suggestion that journalists working for The Observer accessed my bank account details in 1999. Could you please let me know if there is any truth or substance in these claims?"
A spokeswoman for The Observer said that on the basis of the information supplied by Salmond, they had been unable to find any evidence to substantiate his allegation.
She added: "As our response to him at the time made clear, we take this allegation very seriously, and if he is able to provide us with any more information we will investigate further."
A Labour spokesman said: "The First Minister has stated that the source of this information is a former Observer journalist.
'While we appreciate the First Minister's desire to preserve the anonymity of his source, as one of his most senior aides, Alex Bell, is also a former Observer journalist, it is likely that people will jump to possibly erroneous conclusions.
"In the interests of clarity we believe the First Minister should confirm that Mr Bell is not the source of these allegations."
Salmond's spokesman responded to that by saying: "The First Minister was given the information in confidence, which he will respect, and therefore we will not indulge in a guessing game or a process of elimination on this matter."