The move follows the appointment of head of external affairs Barry Gardner from HBOS.
Clydesdale’s affected agencies are College Hill (corporate and financial), Beattie Communications (business) and Ptarmigan (retail).
Lexington Communications, which was recently appointed to advise Clydesdale on PA, is unaffected.
Gardner replaced Tim Pie, now chief press officer for personal finance at HSBC. Gardner reports to head of corporate affairs Guy Williamson.