Portobello Antique Dealers' Association chairman Costas Kleanthous has long feared such a move, which he believes would set a precedent for landlords to bring in alternative tenants to squeeze out antiques dealers. And he has put Kensington and Chelsea Council on notice that granting permission would risk bringing about the end of the world-famous antiques enclave.
"There is no way that the antiques dealers can trade seven days a week," he told ATG. "At the moment, antiques dealers spend most days of the week buying stock from auctions and other sources which they then offer at Portobello on Fridays and Saturdays. Seven-day opening would prevent them from doing this, forcing them to quit the arcade."
He also fears that once the Admiral Vernon Arcade – which he dubbed an "anchor antiques arcade" for Portobello – won permission for seven-day-a-week trading, it would not be long before it spread to the rest of the area, cutting out the antiques trade for good.
In a letter of objection to Kensington and Chelsea Council, Mr Kleanthous writes: "If the council was to grant this application, it would enable the owners to put the ground floor and the basement on the market as they did with Lipka's Antiques Arcade, now an All Saints clothing store. Because of the high footfall at the weekend, this will attract another chain retailer with a devastating blow to the antiques market from which it is unlikely to recover."
It's a view shared by Save Portobello campaigner Marion Gettleson, who has traded from Portobello for 50 years. Along with Mr Kleanthous and other local interest groups, she has objected to the application, which seeks to set aside restrictions imposed on the use of the arcade when the basement was dug out for additional space in the 1990s.
One restriction states that trading should be limited to Fridays and Saturdays "to safeguard the amenities of neighbouring properties".
What makes all this worse, says Mrs Gettleson, is that the application has been made without the applicants or Kensington and Chelsea Council consulting those most affected: the freeholders, Octavia Hill Housing Trust, the residents of the 18 properties above the arcade, or the residents of nearby Vernon's Yard.
The outcry comes as a bid for retrospective planning permission concerning the fascia of the former Lipka's Arcade, now the massive All Saints store, has gone before the council.
In April last year, a mass of protestors packed the council chamber to hear the planning committee denounce the new shop frontage on the corner of Portobello Road and Westbourne Grove as unacceptable. All Saints were given six months to replace what was seen as a design that was inappropriate in scale, scope, design and use of materials.
That ruling ran into problems pending an appeal, and now a new application seeks to water down the alterations. Some of those objecting believe this proposes an even worse design for the section that runs along Portobello Road.
That planning decision is due to be taken by the Council on March 9.
By Ivan Macquisten