A short statement from the Met said: "SO6 is investigating allegations of fraud at City Financial Partners, based in Russell Square, WC1. A man now aged 40 has been arrested and bailed." Police will decide next month, when they next interview Mr Robertson, whether to bring charges of fraud. No wrongdoing has so far been established.
It is understood that the allegations relate to an account held with Fidelity, the US fund manager, in Mr Robertson's name. He allegedly used the fund not for his own benefit but to pay top-ups on surrendered policies which contained less than clients had believed.
City Financial Partners, seen in the industry as the epitome of a 1980s, sales-driven operation, was last month bought out by Lincoln, the UK operation of giant US insurer Lincoln National. Simon Ingram, City Financial's chief executive, is soon expected to take up a new role with Lincoln.