Negotiations continued as some members of the government, including transport minister Norman Baker, appeared willing to quit rather than back the increases.
Mr Clegg will meet with his parliamentary party tonight when he is expected to urge them to present a united front.
Lib Dem grandee Lord Ashdown has also appealed for members not to breach the coalition agreement by voting against the plans on Thursday – but there are signs that opposition within the party was hardening.
Asked whether he would be backing the change or abstaining, Mr Baker told the BBC: ‘Or voting against. There are three options and, to be honest with you, I genuinely haven’t decided. It’s an option if you resign.’
Mr Clegg and business secretary Vince Cable have publicly stated they would like to vote for the package, which trebles the maximum annual charge to Ã‚Â£9,000.
The confirmation in the the increase of tution fees will undoubtldey casue more chaos for the governments, and university around britian as student react against the proposal.
The government maintain the view that the fee increase will be beneficial in the long run, as it will act to increase the skills of the future workforce.