Campaigners are due to learn whether or not they have won a High Court challenge over plans to build a national Holocaust memorial next to the Houses of Parliament.

A judge’s ruling over legal action brought against planning permission for a park site in central London is expected to be delivered on Friday.

The London Historic Parks and Gardens Trust is opposed to a new UK Holocaust Memorial and Learning Centre being built in Victoria Tower Gardens, a small triangular Grade II-listed park next to Westminster Abbey and the Palace of Westminster.

The charity brought a High Court case against the Government, arguing that the project is the “right idea, wrong place” and that the planning permission decision-making process was flawed.

At a hearing in February, the trust, whose bid to quash the decision is opposed by ministers, focused its arguments on the evaluation of alternative sites and the impact the development may have on the heritage setting, including the Buxton Memorial which celebrates the abolition of slavery.

Campaigners claim the memorial’s proposed location risks affecting the park “irrevocably” and have previously raised concerns over the alleged impact on local trees, potential flooding, and heritage monuments.

Lawyers for the Government argued that there was “no error of law” in the decision-making process and that policy had not been “misinterpreted or misapplied”.

Planning permission for the memorial was granted last July by then-planning minister Chris Pincher following a public inquiry and the recommendations of planning inspector David Morgan.

It came after the Government “called in” the decision in November 2019 rather than have it determined by the local authority – Westminster City Council.

The council is among a number of high-profile organisations and individuals to have objected to the chosen site, including former Archbishop of Canterbury Rowan Williams.

The memorial, due to open in 2024, will be the focal point for national remembrance of the six million Jewish men, women and children murdered in the Holocaust and all other victims of Nazi persecution, along with providing a place for reflection on “subsequent genocides”.

It is due to feature a single-storey pavilion and 23 bronze fins that will create 22 pathways into the below-ground learning centre, with the Government committing to it being free to enter “in perpetuity”.

Some £75 million of public money has already been put towards construction costs, which is due to be supplemented by £25 million from charitable donations.

Mrs Justice Thornton is due to deliver her judgment at 10.30am on Friday.