The chairman of PLUS Markets, the junior London stock exchange that is home to football club Arsenal, has decided to leave the group following pressure from one of the exchange's major shareholders for a boardroom shake-up after mounting losses at the company.

Middle East investment group Amara Dhari, which holds some 17 percent of PLUS Markets, had called for the resignation of Giles Vardey, and PLUS Markets said on Thursday that Vardey had now decided to quit.

PLUS Markets Group Plc wishes to announce that Giles Vardey has taken the decision to step down as Chairman and non-executive director with immediate effect, for personal reasons, it said in a statement.

It added it had begun looking for a new chairman and that Malcolm Basing would become its interim chairman for the time being.

Plus Markets grew out of the old Ofex, an alternative stock market requiring a lower level of regulation than is imposed by members of either AIM or the London Stock Exchange.

(Reporting by Sudip Kar-Gupta; Editing by Jon Loades-Carter)