Liberal Democrat deputy leader Simon Hughes has rejected accusations of hypocrisy over tuition fee hikes after accepting a job advising the Government on access to education.
The MP, who abstained in the key Commons vote on the controversial issue, said he still "regretted" the decision to treble the maximum charge to £9,000.
But he insisted he wants to help make sure bright students from poorer backgrounds feel able to go to university in spite of the potentially huge bill.
Mr Hughes mounted his defence after being appointed as the Government's Advocate for Access to Education by Prime Minister David Cameron and his Lib Dem deputy Nick Clegg.
Labour condemned the move as a sop from the Tories to soothe their coalition allies' concerns over tuition fees.
But Mr Hughes stressed he would remain an independent voice during the six-month appointment, and is still prepared to criticise the policy. "I am not there in a way to sell it, I am there to make sure people understand the facts," the backbencher told BBC Radio 4's World at One.
"I wouldn't vote for it because I believed that with the higher rate that could go, in some cases, up to £9,000 a year, that could put people off applying to university. The problem with the system is the perception rather than the reality."
He added: "I am a member of a party that has believed, and still believes, that we should ideally not have tuition fees. That's been our view and it remains the Liberal Democrat view. We didn't win the election, we had to negotiate a coalition with the Conservatives.
"Both other parties had actually signed up to tuition fees so it would have been similar if Labour had been the coalition partner."
Asked on Sky News whether he was abandoning his principles by taking the job, he said: "No, it is not hypocritical." As part of his unpaid role, Mr Hughes will also contribute to work on replacing the Education Maintenance Allowance - the axing of which he has criticised.