A HOLLYWOOD actress has won planning permission to build a “tranquil retreat” at her multi-million pound manor - despite the discovery of a colony of bats at the site.

Cate Blanchett intends to demolish a cottage and shed on the grounds of her £4.9 million home in Crowborough and replace them with a contemporary garden office and studio, including a meditation room.

But the 51-year-old two-time Oscar winner must now submit a “bat mitigation strategy” before any work is carried out, after evidence of the animals was found at the site.

According to planning documents lodged with Wealden District Council, return-to-roost surveys and DNA analysis of droppings confirmed “the presence of a common pipistrelle bat summer roost and a potential occasional brown longeared bat feeding roost”.

Common pipistrelle bats and brown longeared bats are both considered to be protected species and any buildings containing a roost cannot be demolished without a licence from Natural England.

The plans to demolish the garden buildings have now been approved, but the council states: “Prior to the demolition of any of the existing buildings on site, a bat mitigation strategy shall be submitted to and be approved in writing by the Local Planning Authority.

The Argus: A pipistrelle bat. Photo: PAA pipistrelle bat. Photo: PA

“This shall include details of the mitigation and compensation measures to be adopted and details of the European Protected Species licence.

“This is to identify and ensure the survival and protection of important species and those protected by legislation that could be adversely affected by the development.

“Works shall thereafter be implemented in accordance with the approved details.”

Ms Blanchett’s planning agent told The Sun newspaper: “The proposed building will be a place for the applicants to retreat for work and relaxation.

“They are creative people and it is beneficial for them to have a place to work that is tranquil and inspires through the beauty of the art, architecture and landscape setting.”

The mansion, which the Australian star shares with her husband Andrew Upton, was built in 1890 and is the former home of Sherlock Holmes creator Sir Arthur Conan Doyle and Doctor Who star Tom Baker.

The Argus: Actress Cate BlanchettActress Cate Blanchett

Highwell House boasts seven bedrooms, five reception rooms and a lookout room in the house’s castle-like turret.

The Lord of the Rings star reportedly bought the mansion in 2016 for more than £3 million. The property has 13 acres of land, including a lavender garden and several outbuildings.

In June last year the actress revealed she had a DIY accident with a chainsaw at the mansion, but only suffered “a little nick” on her head.

Ms Blanchett also previously owned a property in Lewes Crescent in Brighton in the early 2000s.