Prince Charles’s favourite architect Quinlan Terry has been fined £25,000 for knocking down two grade II listed buildings – designed by another renowned architect.

Terry, who has worked on 10 Downing Street, sent demolition teams in to knock down North Lodge and South Lodge in the grounds of John Nash’s Hanover House in Regent Park in December last year.

The destruction, part of modernisation works at the Crown Estate property, far exceeded the permission granted to Terry in the application for alterations.

Terry was taken to Westminster Magistrates’ Court by Westminster City Council where he pleaded guilty to three charges under the Planning Act 1990.

‘Westminster has a rich architectural heritage and it is the council’s duty to protect this for future generations,’ said Westminster Council’s cabinet member for planning, Cllr Robert Davis, said. ‘For one of the country’s pre eminent architects to fall foul of the law is disappointing, but I hope the size of the fine will send a very clear signal to anybody who thinks they can damage or destroy listed buildings without regard, whoever they may be.’

All that was left of the two buildings was the rear walls, with the roofs and the rest of the buildings turned into rubble.

Contractors Walter Lilly & Co, which was responsible for the construction site, was fined £20,000 after pleading guilty to committing two offences for the demolition of each lodge. Both the contractor and architect were also ordered to pay more than £5000 costs by the City of Westminster Magistrates' Court.