A development firm planning to turn a country house into luxury flats has been accused of resorting to “petty” tactics.

CHB Developments, which owns the A-listed 34-room Cumbernauld House in Wilderness Brae, lodged a complaint to the Office of the Scottish Charity Regulator about the name used by a group which wants to save the house for public use.

The letter to the regulator claims the name, “Cumbernauld House Trust,” may cause people to believe the Trust owns the property or is connected with CHB Developments.

But the Trust described the move as “petty and desperate” and said Cumbernauld House Trust was set up four months before CHB Developments was registered as a business with Companies House, the UK register of businesses.

Lynn Ferguson, the writer and actress best known for her work as the voice of Mac in the film Chicken Run, is patron of the Trust.

She branded the complaint a “ridiculously aggressive act” and urged local people to object to the planning application.

She said: “A formal objection to the charity’s name, really? Oh grow up.

“If my mother was still alive would they be calling her up and telling her I don’t have my vest on?”

The 279-year-old mansion is a three storey building with a basement level and two two-storey wings linked to the main structure. There are also stables, a yard and various outbuildings.

CHB wants to build 10 homes at the site – four flats in the house itself while the annexe buildings would be converted into two homes.

The courtyard cottages would also be turned into two houses and a further two new-build houses would be added in the courtyard.

The Trust says the house should never have been sold to a private company in the first place and should be retained as a community hub.

Adam Smith, of the Trust, said: “This complaint to the regulator seems like a desperate and petty move on the part of CHB Developments. No one is likely to confuse us with CHB.”

The council’s planning department is set to decide on the application on January 26 and objections can be lodged up until January 7.

Around 50 objections have been lodged so far. Complaints can be lodged through the website www.cumbernauldhousetrust.org.uk, which has a link to the council’s planning application website.

CHB Developments declined to comment.