Distinctive Properties Ltd, the developers behind the controversial plan to build a mansion in Blacknest Park, will now have to replant a total of 1,280 trees by February 19, 2016, after their appeal against a replacement notice (TRN) was dismissed by a high court judge.

In their claim, the developers disputed the number of trees they had been told to replant on the site, claiming only 27 trees were cut down in April and May 2012, but Justice Holgate concluded that there was “no merit in any of the grounds put forward”.

Dr Andrea Berardi, a long-time campaigner against the development and owner of neighbouring Granny Kettle Woods, was delighted at the high court’s decision.

“I am absolutely over the moon, this is more than three years of fighting and it’s all over for the developers now, they have to replant the trees. It’s big news for the trees and lovely plants and animals,” he said. The TRN was issued by the Royal Borough in January 2014. It ordered Distinctive Properties to replant trees in part of the protected woodland off Whitmore Lane within 24 months.

Douglas Bond, agent for Distinctive Properties, said: “They are unlikely to make a comment at the moment. I couldn’t tell you what the next steps are.” The original plans to build a £20million Georgian mansion on the site were unanimously rejected by a Royal Borough planning committee in June 2013.

Councillor Derek Wilson, Royal Borough member for planning, said: “We welcome the judge’s decision regarding the tree replacement notice. We will now await the outcome of the public inquiry regarding the council’s refusal of planning permission for a mansion at the site.”