Lloyds has been told to divest itself of 600 branches. Sir John, whose Commission has been told to come up with proposals to make the UK's banks safe in future and beef up competition, has already said that won't be enough.
Today he reiterated to MPs on the Treasury select committee that he was "clear that there should be a substantial enhancement" of the 600 figure, though it would be "inappropriate" come up with an exact number.
Selling 600 branches would reduce Lloyds Banking Group's share of personal accounts from 30% to 25%. But Sir John said it was a major issue that one institution could have a quarter of all accounts.