Part of Syrian-born billionaire Simon Halabi's property empire is to be put on the block to pay back debts, after the buildings fell into negative equity.
Ernest & Young has been appointed by the High Court as the administrators for the six buildings, which are: the Aviva Tower, in the City of London; JPMorgan's offices at 60 Victoria Embankment; New Court, in Carey Street; Millennium Bridge House; Ludgate House, on Bankside; and Leadenhall Court, in London. Together they are worth around £500m.
It is understood that the administrators have three years to sell the properties, but that the disposals are likely to occur much sooner.
HM Revenue & Customs recently ordered the liquidation of the companies that own the buildings, after chasing £4.8m in overdue tax.
A senior loan of £1.15bn, due to mature on October 23, had been secured against the properties, but will prove too difficult to refinance after a sharp decline in value of the buildings.
The entire portfolio of nine properties is now worth £929m, and is owned through several companies. Mr Halabi owns shares in 30 different companies, and ranked fourteenth place on the Sunday Times Rich List in 2007.