A bankrupt Tory donor and close political ally of Foreign Secretary William Hague, whose business empire was put into administration, has gone missing, according to a judge.

The claim came at the end of a case in which former Scottish Tory treasurer Malcolm Scott and his wife were found liable for around £740,000 in landscaping costs.

Scott’s wife Rona herself now faces sequestration – the Scots term for bankruptcy – a fate that has also befallen the Tory businessman’s mother and father. Labour MP Graeme Morrice said the “mystery” of Malcolm Scott’s whereabouts must now be “cleared up”.

For around five years, Scott was one of the biggest Tory donors from north of the Border, ploughing in over £1.6 million to the party.

He had close links to several Westminster Tories, particularly Hague, and as Scottish treasurer had responsibility for the party’s financial stewardship.

However, Scott’s riches turned to dust last year after his grain and property businesses were put into administration. His firms struggled to repay millions of pounds owed to banks, Scott was made bankrupt, and the administrators launched a probe into his assets.

The mystery surrounding Scott’s location was discussed at a Court of Session hearing on Wednesday.

Courseworks Ltd, a garden design firm based in Nottingham, took Scott and his wife to court last year over unpaid landscaping work in the grounds of his sprawling mansion in Kirknewton, West Lothian.

According to court documents, Courseworks estimated that the total value of the work, together with the costs associated with the cancellation of the contract, came to £2,293,188.76.

Although £1.8m had been paid, Courseworks successfully went to court in October over the remaining £550,059.

By the time of last week’s hearing – relating to the processing of court expenses – interest charges had taken the bill to around £740,000.

The hearing was called after the Courseworks legal team was unable to serve the Scotts with the paperwork for the final expenses account.

Judge Lord Drummond Young said it appeared the “defenders have disappeared”, adding that it looked like they were “trying to avoid contact” with the firm’s legal representatives.

The Scotts no longer live in the Kirknewton mansion – a property that has struggled to find a buyer – and the pair were subsequently linked to Edinburgh’s upmarket Barnton Avenue.

Their current location is unknown, but the Sunday Herald spotted Malcolm Scott at the Sarti cafe in Glasgow last month.

The court papers also supplied a breakdown of some of the landscaping work on the property, which has nine bedrooms, six reception rooms, eight bathrooms, a swimming pool and a tennis court. The Courseworks list included £16,574 for a boathouse feasibility study, £21,415 for a walled garden greenhouse base, £72,473 for electrical work, and £15,548 for a tennis court wall.  

The ledger also included £21,331 for “York stone columns and oak courtyard”, £19,384 for a driveway upgrade, and £22,396 on a “pergola upgrade”.

Another £3290 of work was carried out on a “lake survey” and another £1500 went on bark.

Courseworks has now lodged a creditor’s claim with the trustee dealing with Malcolm Scott’s sequestration.

Scott’s wife faces a similar outcome, as a petition for her sequestration was recently lodged by the garden firm.

Legal papers state that 27 Barnton Avenue was her “last known address”.

Separately, the tycoon’s parents were made bankrupt last year after they tried to guarantee their son’s debts for £10m each.

Labour MP Graeme Morrice said: “Most people would find it surprising that anyone could spend hundreds of thousands of pounds on landscaping. However, people won’t find it surprising that such a man could end up as the Scottish Tory treasurer. The mystery surrounding Malcolm Scott’s whereabouts should be cleared up as soon as possible.”

An SNP spokesperson said: “The longer this sorry affair drags on, the more questions arise about the way in which the Tories conduct their financial affairs. It is a major headache for the Tories in Scotland and the longer they remain silent on this matter, the worse it looks for them.”

A spokesman for KPMG, which is handling Scott’s bankruptcy, said the firm was “still in the process of investigating the case with a view to maximising recoveries from the key assets”.

A Scottish Tory spokesman said: “Malcolm Scott has nothing to do with the Scottish Conservatives, and these are personal matters for him and his family.”

Scott could not be contacted.