UK trade secretary Alistair Darling has opened a new front in the scrutiny of satellite broadcaster BSkyB's controversial purchase of a stake in UK television channel operator ITV in November, and has given regulators a two-month deadline to report their findings.

Darling, the UK secretary of state for trade and industry, today directed Ofcom, the communications industry watchdog, to start an initial investigation into BSkyB's dusk raid on November 17 that netted the group a 17.9% stake in ITV.