Hearts chief's £20m buy has been sitting empty for three years

The Scottish Civic Trust, which compiles the list on behalf of Historic Scotland, said that the former headquarters of Royal Bank of Scotland at 42 St Andrew Square is starting to show "some signs of deterioration".

It also said there were now "signs of vandalism" at the building – which Romanov's investment company UBIG bought in 2007. UBIG today confirmed that it intends to press on with plans to develop the building and aims to submit a new planning application later this year.

However, the Lithuanian firm revealed it has dropped plans to turn it into a luxury hotel and will instead upgrade it and reopen it as an office.

Vitalijus Vasiliauskas, UK projects director for UBIG, said he was not aware that the building was judged to be "at risk", but insisted the company was keen to start work as soon as possible.

"We have a plan for the building," said Mr Vasiliauskas, who is also Hearts' infrastructure and development manager and is responsible for the plans to expand Tynecastle Stadium.

"We have changed the original concept and are now proceeding, although not as fast as we would like. It will become offices now, not a hotel.

"A team of architects are preparing plans and everyone will be informed as soon as possible about our plans."

UBIG (Ukio Bankas Investment Group) bought the building in 2007 for 20 million in a move that raised eyebrows even although it was at the height of the property boom.

City centre councillor Charles Dundas said: "You only have to look at the (Lauriston United) church on Lauriston Place to see the state buildings left in disrepair can get into.

"Everyone would want a building in such a prominent place to have a use, not least the owners."

Stewart Taylor, a director of business space at property firm CB Richard Ellis, said: "As far as the location and profile is concerned, you would have thought that hotel would be the best use."

And he hinted that its place on the "at risk" register could actually help speed an application through the planning process.

A spokeswoman for Historic Scotland said: "There are no immediate concerns for the building as the register has identified the building's risk is moderate and its current condition as fair.

"We are currently awaiting proposals for the building and hope to see its sensitive re-use."

The latest Buildings At Risk Register includes 29 A-listed buildings in Edinburgh. The City Observatory on Calton Hill – itself earmarked for development into a hotel – and the TopShop building on Princes Street, where many floors are unused, are among those to make the list.

A city council spokesman said: "The council will continue to monitor the condition of these nationally important buildings."

THE CRUMBLING CAPITAL

What the Scottish Civic Trust said about some of the A-listed buildings in Lothian considered at risk:

Acheson House, High Street: "Roof and other elements are deteriorating."

City Observatory, Calton Hill: "Remains a target for thieves stealing lead sheets from the roof."

4-5 Baxter's Place: "Former cinema is closed and boarded up."

Tron Kirk, High Street: "Damaged stones and deterioration evident in some windows."

3/3a St Andrew Square: "Netting across the entire facade at upper levels."

42 St Andrew Square: "Starting to show some signs of deterioration . . . some signs of vandalism."

29-31 George Street: "Upper floors decaying internally."

26-30 Princes Street and 2-6 South St Andrew Street: "Majority of the landmark building is vacant and unused."

Granton Harbour, Middle Pier and Pilot House: "Pier is decaying rapidly."

Warriston Cemetery: "Grounds are heavily overgrown . . . many monuments have collapsed or been subjected to vandalism."

Mortonhall House Burial Ground: "Heavily overgrown with vegetation and subject to extensive vandalism."