Rebel Labour MPs will make their final attempt next week to force the government to abandon plans for variable tuition fees by tabling a radical amendment to the higher education bill.
Ian Gibson, Labour MP for Norwich North, revealed that the rebels will attempt to replace variable fees with a fixed fee when the bill returns to the Commons for its report stage and third reading next Wednesday after a month of clause-by-clause scrutiny by a committee of MPs.
Wednesday's debate will be the final opportunity for MPs to amend or vote down the government's proposals before they move on to the House of Lords.
The rebels will propose turning the existing upfront £1,125 fee into a postgraduation charge, ditching the government's plan to allow universities to charge variable fees of up to £3,000 a year.
Nevertheless, the Labour rebels - who in January staged the largest backbench rebellion of Tony Blair's premiership at the bill's second reading - will attempt to retain the government's proposals for grants for poor students and plans for a new university access regulator.
Although talks have been under way between ministers and Labour backbenchers, there were few signs this week of further concessions before the bill reaches the Lords.
It also remains to be seen if 20 vice-chancellors will carry out their plan to publish a letter of opposition to variable fees to coincide with Wednesday's debate.
The National Union of Students, which is due to hold its annual conference in Blackpool next week, has called the timing of the vote a "cynical ploy" by ministers to hinder opposition. In an unprecedented step, the conference will be suspended on Wednesday to allow activists to lobby Westminster.
The January vote on the second reading saw the government majority reduced from 161 to five votes, with 72 Labour MPs voting against the government and 19 abstentions.
Another amendment from the Labour back benches - tabled by Cambridge MP Anne Campbell and Selby MP John Grogan - would replace variable fees with a fixed fee linked to inflation.
The Tories have withdrawn an amendment that would have "deleted" clauses on fees from the bill, apparently giving ground to Labour opponents of the bill to propose their changes.
Labour rebels came under fire from their parliamentary colleagues in January for being seen to vote with the Conservatives.
Other Tory amendments target the plans of Charles Clarke, the education secretary, for the Office for Fair Access, proposing that the regulator ensure students are recruited on "merit and potential" rather than social background.
The Liberal Democrats have tabled a series of amendments, including a "no-fee" one, one that would relieve graduates in low-paid public service jobs from paying back student loans and a further one that would remove the upper age limit on loans.