Selfridges’ new owners are backing plans by Marks & Spencer to demolish and redevelop its Oxford Street store, with a planning inquiry into the controversial proposals beginning this week. The two-week inquiry, which starts on Tuesday in Westminster, will pit M&S and its Oxford Street neighbour Selfridges against environmental campaigners and historic building fans, who argue that the 90-year-old landmark store should be refurbished rather than knocked down. A spokesperson for Selfridges, which was bought out by the Thai conglomerate Central Group and the Austrian real estate company Signa Holding last month, said the historic department store “supports and endorses” the redevelopment of its neighbour, saying it has a role in “maintaining Oxford Street as the UK’s national shop window”. Selfridges’ comments come in a letter to the Planning Inspectorate overseeing the inquiry, which will put consideration of the carbon footprint of the redevelopment of a major building centre stage for the first time. The inquiry will be overseen by the planning inspector David Nicholson, who recently blocked the 305-metre Tulip tower in London, partly on the grounds that its “highly unsustainable” use of concrete might set a “gamechanging precedent”. The former communities secretary Michael Gove announced an inquiry into the future of M&S’s store near Marble Arch in June after vocal opposition to the redevelopment plan, which had been approved by the local council and the Greater London Authority. Opponents of the redevelopment say the scheme, designed by the architecture firm Pilbrow & Partners, would release almost 40,000 tonnes of carbon into the atmosphere. About 5,000 people have signed a petition by the historic buildings campaign group SAVE Britain’s Heritage against the M&S proposal. Some well-known architects and the author Bill Bryson have also opposed the plans by M&S. Henrietta Billings, the director of SAVE, said the case would be “a major test of our disposable, knock-it-down-and-rebuild attitude to our cities and historic buildings. In the face of a climate crisis, demolition must be the last not the first resort.” The local councillor Jessica Toale, who is a ward member for the West End, has also supported the campaign to save M&S’s existing building, saying it is “well-loved by the community” and “the environmental impacts of plans to demolish the building are considerable”. Westminster city council, which fell to Labour at the local elections after the outgoing Tory administration granted M&S permission to tear down the 90-year-old store near Marble Arch, has welcomed the inquiry. It has said it is “serious about reducing the environmental impact of new development” but is also keen for M&S to stay on Oxford street. M&S argues that a refurbishment of the three poorly connected and low-ceilinged buildings that make up its Marble Arch store is unfeasible and would not achieve the kind of experience modern shoppers want – potentially forcing it to move away from Oxford Street, accelerating the area’s decline. Oxford Street has already endured the exit of the major department stores Debenhams and House of Fraser and dozens of other smaller retailers, with an influx of American candy shops only adding to its down-at-heel feel. M&S says the new development will use a quarter of the current building’s energy, achieving a payback on investment in the first 17 years of its 100-plus years lifespan. The retailer has pledged that 95% of the materials in its existing Marble Arch building will be recovered, recycled or reused. It says some materials would be reused directly on-site within its new building as part of its efforts to “promote circular economy principles”.