Nick Clegg has apologised for breaking an election promise not to increase university tuition fees.
Speaking ahead of the Liberal Democrat Party Conference in Brighton, the Deputy Prime Minister admitted he had broken a pledge not to support a rise in fees, which now cost students up to £9,000 a year.
In a new party political broadcast to be aired nationally on Monday evening, Mr Clegg said: "There's no easy way to say this: we made a pledge, we didn't stick to it - and for that I am sorry."
It is the first time Mr Clegg has apologised to his party for breaking the election pledge. But aides close to the Deputy Prime Minister insisted he was not apologising for supporting the policy through Parliament but only for promising to vote against any prospective rise in tuition fees as he fought the 2010 General Election.
In the video clip to be broadcast on Monday, Mr Clegg admitted many voters had "strong and pretty mixed feelings" about the Liberal Democrats record in Government, adding his party had put aside political differences to "provide our country with stable leadership".
He said: "I also meet people who are disappointed and angry that we couldn't keep all our promises - above all our promise not to raise tuition fees.
"To those people, I say this: we made a promise before the election that we would vote against any rise in fees under any circumstances.
"But that was a mistake. It was a pledge made with the best of intentions - but we shouldn't have made a promise we weren't absolutely sure we could deliver.
"I shouldn't have committed to a policy that was so expensive when there was no money around. Not least when the most likely way we'd end up in Government was in coalition with Labour or the Conservatives, who were both committed to put fees up.
"I know that we fought to get the best policy we could in those circumstances. But I also realise that isn't the point. There's no easy way to say this: we made a pledge, we didn't stick to it - and for that I am sorry."