STEFAN King's leisure empire has been banned from carrying out alterations at one of Glasgow's most historic buildings.

An interim interdict has been awarded following fears ceilings could crash and floors sink during the ground-floor conversion of two retail units within the three-storey Victorian building in Royal Exchange Square.

The legal action came after tradesmen moved in on Tuesday to start work on creating a cafe bar, restaurant, and function suite next door to Mr King's Babaza nightclub.

His G1 group paid (pounds) 1.7m for the two units, a former building society office and hairdressing salon which is still trading.

Proposals include opening up an interior wall to allow direct links from the cafe and restaurant to the basement disco.

Babaza used to be Club X, one of Glasgow's first openly gay venues, whose success led to Mr King's meteoric rise and personal fortune estimated at (pounds) 12m.

However, Glasgow Sheriff Court has now been told that when Club X was created in 1989, a section of wall was removed, leading to ''catastrophic consequences'' on upper floors.

Huge cracks appeared on walls, while floors dropped by three inches, with occupiers of the top two floors decanted while repairs were carried out. Following legal action at that time, the Court of Session ruled the work had amounted to a nuisance. It is understood 10 years passed before insurers for structural engineers paid out a reputed (pounds) 250,000 in connection with the damage.

In the latest court case, Anne Kennedy, who owns offices directly above the units taken over by G1, sought the interdict over concerns of a repeat if load-bearing walls were altered to make way for the new development.

Sheriff Fiona Reith was told G1 proposed to open up a wall in the grade A listed property, built in 1838.

It was argued the wall was the same as that in 1989 when subsidence followed a section being opened by a company called Glenbelle Ltd, directed by Mr King.

The court was told no building warrant had been granted, and in its absence any alterations would be illegal.

The interim interdict prevents G1 or others acting on its behalf from making structural alterations on load-bearing walls pending the warrant.

Ann Kennedy's husband Ewan, a lawyer who is a tenant on the second floor, said yesterday: ''We felt it necessary to take action after what happened in 1989, to protect interests of her property and that of tenants.''

Jim McMillan, G1's contracts manager, last night insisted the court action was unnecessary because alterations are at ''a ridiculously early stage''.

He added: ''It was brought about by neighbours who completely jumped the gun.''

Glasgow City Council has approved listed building consent, partly on grounds it wants to encourage a ''cafe culture'' in Royal Exchange Square.