CELTIC’S main shareholder, Dermot Desmond, has become the latest high-profile figure to be linked to the leaked Panama Papers as David Cameron came under intense political pressure to provide full transparency on his financial interests.

Nicola Sturgeon said the Prime Minister, the son of a Scottish stockbroker, had, by his obfuscation, “brought politics into disrepute” while Jeremy Corbyn accused him of “misleading the public about his personal involvement in offshore tax avoidance schemes”. Both the SNP and Labour are now demanding the Conservative leader make a Commons statement on Monday to provide “full transparency”.

Today, some 2000 people are said to be preparing to demonstrate outside Downing Street, calling on the Tory leader to resign; they are expected to include singer Lily Allen and comedians Mark Thomas and Josie Long.

Several rich and famous people, including golfer Sir Nick Faldo, Baroness Thatcher’s son Sir Mark and X Factor judge Simon Cowell, have been named in the 11.5 million files leaked from the Panamanian law firm Mossack Fonseca, revealing how they had used numerous tax havens to shield their wealth from the public eye.

The latest prominent figure to emerge from the files is Mr Desmond, the 65-year-old Irish billionaire.

His name is reportedly contained in paperwork going back to 2005 between HSBC Private Bank in Switzerland and Mossack Fonseca.

It relates to a firm called Ard International Inc, whose directors grant Mr Desmond legal authority over the company.

A few months later, however, a note from the Caribbean-based tycoon asked that Ard’s directors instead grant power of attorney to two Swiss lawyers.

It said: “This being done, I resign as attorney of the above-mentioned company and ask you to kindly destroy the document of my appointment and the one of my resignation.”

There is no suggestion that Mr Desmond or anyone else named in the papers has broken the law in any regard. He was approached for a comment but his spokeswoman said the tycoon did not wish to give one.

Celtic FC was also approached for a comment but likewise declined. However, Jeanette Findlay of the Celtic Trust, which represents supporters, said: “The Trust’s primary motive for existence is to promote the good governance of Celtic Football Club.

“We are on record as having opposed previous chairmen and directors for activities we felt were not aligned to the ethos of the club. If Mr Desmond or any other director was found to be involved in any tax-dodging scheme, we would have grave concerns about that,” she added.

Paul Brennan, who runs Celtic Quick News, one of the biggest supporter online sites, stressed: “The club is not linked to the Panama Papers issue; Mr Desmond has been linked to the Panama Papers issue. If he has done anything inappropriate, he should be called to account for it.”

Any hopes that Mr Cameron might have had that his admission - that he had profited £19,000 from an offshore fund based in the tax haven of Panama albeit having paid full tax on his gains – would draw a line under the issue were swiftly dashed.

The First Minister noted: “Whether or not it was legal, the tortuous way the information was dragged out of the Prime Minister leaves his credibility in tatters and completely betrays public trust.”

The Labour leader, who will take to the Holyrood campaign in Scotland today, also upped the rhetoric, saying: “It is now clear the Prime Minister has misled the public about his personal involvement in offshore tax avoidance schemes.”

Denouncing the Tory leader’s “weasel-worded statements”, Mr Corbyn declared: “The Prime Minister has lost the trust of the British people. He must now give a full account of all his private financial dealings and make a statement to Parliament next week. Only complete openness from the Prime Minister and decisive action against tax avoidance and evasion can now deal with the issues at the heart of this scandal.”

Labour backbencher John Mann raised the prospect of Mr Cameron facing a parliamentary probe, saying he intended to report the PM to the parliamentary standards watchdog for not declaring his stake in an offshore fund; while ex-London mayor Ken Livingstone went further, declaring: “He shouldn’t just resign; he should be sent to prison.”

Meantime, Tory colleagues came to their leader’s defence. Business Minister Nick Boles said "with the benefit of hindsight" it might have been better if the PM had revealed details of his shareholdings when the allegations first surfaced on Monday but he said he understood Mr Cameron's "natural human instinct to rally round his father".

Conservative backbencher Mark Pritchard denounced Labour’s attacks as “distasteful” and said the PM had been the victim of a “real injustice”.

“He has said that he will publish his tax returns. He’s been very, very open about his property ownership, his other ownership. I don’t think he should be discriminated against just because he was born into a wealthy family,” added Mr Pritchard.