North Norfolk MP Norman Lamb has admitted the Liberal Democrats' positioning on student fees has been 'messy', as confusion continued over which way the party's 57 MPs will vote.

Mr Lamb, who is chief political adviser to Deputy Prime Minister Nick Clegg, said that it was the 'strong preference'' of both him and Mr Clegg to back measures which would almost treble the maximum university tuition fee to �9,000, but added that they would respect the collective decision of the parliamentary party, which meets tomorrow.

His comments came amid reports of angry exchanges between Mr Clegg and Business Secretary Vince Cable, who has responsibility for getting the proposals through Parliament.

Mr Cable last week said he had 'no doubt'' he would vote in favour of the reforms, before swiftly backtracking and saying he would abstain if all his parliamentary colleagues agreed to do so.

The mass abstention option was put forward in a bid to prevent a three-way split in the party in Thursday's Commons vote, with former leaders Charles Kennedy and Sir Menzies Campbell otherwise expected to be joined by several backbenchers in voting against the Government.

But it has magnified the sense of confusion surrounding the Lib Dems, who have come under intense pressure from students angry at their failure to live up to a manifesto promise to abolish fees.

Mr Lamb told BBC1's The Politics Show: 'This is difficult, it's messy ... My very strong preference, as is the case for Nick, is to vote in favour ... (but) we have clear processes. Nick is very keen that he engages with the parliamentary party. We will make our final decision when the parliamentary party meets.''

In a last-minute bid to shore up support for the reforms, ministers this week unveiled proposals for disadvantaged students to receive at least one year's free tuition.