Lyons did not rule out the possibility of closing down either digital channel BBC Three or BBC Four, in interviews in the national press marking his first 100 days chairing the BBC Trust. However, a measure as drastic as a channel closure is unlikely.
In one newspaper interview, Lyons said: "Have we ruled out radical changes? No, we haven't. It is about what you can afford to do with the money you've got."
He said that he would be examining cost-cutting plans this autumn; over six financial years, from 2007 to 2013, the BBC needs to save £2bn.
Lyons also acknowledged that the BBC needed to rebuild trust among viewers following a series of revelations that producers had fabricated competition winners on shows including 'Children in Need'.
He added that the BBC Trust might take further action over the so-called "Queengate" scandal, which arose when it was revealed that a scene in a fly-on-the-wall documentary about the Queen had been faked. The footage appeared to show the Queen storming out of a session with photographer Annie Leibovitz, when the scene was actually filmed before the meeting.
Lyons was asked by The Times whether he thought the BBC One controller Peter Fincham should have personally checked the veracity of the clip. He replied: "Do I personally think it was reasonable to check something that was so newsworthy? Yes, I do."