Ofcom was at liberty to investigate the issue of "fit and proper" at any time, he added, but would also have to take into account any subsequent undertakings negotiated by the Competition Commission.
In a strongly-worded response, the chancellor will say that, under the deal negotiated by his predecessor Alistair Darling with the European Commission over state aid to banks, the government had to sell the majority of its stake by the end of 2013.
"In view of this considerable opposition, it is clear that the European Commission must step up efforts to find a negotiated solution, " the person said.