In addition to the original building, there is also an 3,500 square metres (38,000 square feet) annex built in 1993, an ancillary structure housing office security services and a bomb shelter predating the 1990s.[7] The building, formerly known as Villa Zagorje or Tito's Villa, was designed by architects Vjenceslav Richter and Kazimir Ostrogović and completed in 1964 for the former Yugoslav president Josip Broz Tito.[7][29]