Derwent London has confirmed it is planning to convert to tax-efficient real estate investment trust (REIT) status on July 1, 2007. The group will be required to pay a one-off charge calculated. Set at 2% of the group's gross qualifying assets, this comes to £46 mln (EUR 71 mln). Derwent London was formed by the merger of Derwent Valley Holdings with London Merchant Securities last February.