The BBC will be scrutinised by millions of people during the EU referendum, a trustee at the broadcaster's governing body has said.
Richard Ayre said viewers and listeners will be "more than ready" to point out when they believe the corporation has not acted impartially, while BBC Trust chairman Rona Fairhead said impartiality is "absolutely critical".
She said staff at the BBC are being trained in the run-up to the referendum to ensure they understand all the issues so that the coverage is "as fair and as impartial as possible".
Last month, the Trust and Ofcom responded to a letter from Culture Secretary John Whittingdale asking them how they intend to redress ''lapses in editorial judgment'' during the in-out EU referendum campaign by insisting they will remain neutral.
In October, the BBC was accused of peddling more ''half truths and lies'' than the Nazis as SNP activists vented their anger at its perceived bias against Scotland and independence.
Feelings were still running high over what pro-independence campaigners believed was a pro-Union slant to the public service broadcaster's coverage of last year's referendum, and it culminated in street protests targeting then BBC political editor Nick Robinson.
Talking about the BBC's plans ahead of the EU referendum, Fairhead told the European Scrutiny Committee: "We think it's fundamental that a reasonable person looking at this will say that the BBC has absolutely done everything it could to make sure that it was broadly balanced."
She said of impartiality: "We think it's an absolutely critical value and critical part of the BBC. When we ask the public what is important about the BBC, it is that it's seen to be independent and impartial."
Richard Ayre, a trustee at the BBC Trust, added: "If you're question is 'does the BBC Trust and does the BBC Executive recognise that in the run up to and during the EU referendum the BBC will be under ever more scrutiny, possibly more than in its post-war history?' Yes, yes, we absolutely do. The scrutiny, in my submission, will come from 50m people who watch and listen to our programmes, and will be more than ready to tell us when they think the BBC has not acted impartially."
Fairhead said the Trust understands the need to have due impartiality at the BBC, describing it as a "fundamental part" of having a news organisation that is trusted.
"And that is why there is so much effort put into those guidelines, why we do these impartiality reviews which do take some considerable amount of time and money… because they have to be done thoroughly and properly. But we think that's the only way to make sure that impartiality is both there and seen to be there. So that's why this is taken very seriously," she said.
Ayre said the broadcaster is in "the final stages of devising a matrix of training" with the intention of it reaching every single BBC journalist.
Fairhead said: "People need to be aware of the issues, and understand the complexity of the issues so that the coverage is as fair and as impartial as possible. And that they understand all the issues in that referendum."
She said from what the Trust has seen the BBC is actively working at making sure the training is fit for purpose, and is working on the assumption that the referendum could happen at any time.
"It's better to have the urgency now so that it's locked in and then when the time comes… we don't even know how long the referendum period will be," she said.