Leading Liberal Democrat Norman Lamb has told of his 'moral dilemma' after admitting he was set to break a pre-election promise to oppose higher university tuition fees.

In an exclusive EDP column, the North Norfolk MP and chief political adviser to Lib Dem leader Nick Clegg said he was 'positive' about the controversial govern-ment proposals for a near three-fold increase in fees to �9,000 per year.

And, despite having joined scores of Lib Dems in signing a pre-general election pledge to oppose any increase, he said: 'I certainly won't be in a position of voting against this.'

Mr Lamb admitted he regretted signing the pledge, but said the Lib Dems' position as junior partner in the coalition government with the Conservatives had led to the proposed introduction of a 'fairer system' than at present.

And he spelled out a host of reasons why he supported many aspects of the proposed new system, saying 'those with the broadest shoulders will bear the heaviest burden'.

Mr Lamb's views, which are outlined fully in his column on today's EDP page 17, will not go down well with student activists, who have promised to target any Lib Dems who go back on their pledge.

Pressure is mounting on Norwich South Lib Dem MP Simon Wright after the National Union of Students (NUS) set its sights on triggering a by-election to oust him because of the expected U-turn on tuition fees.

However, Mr Wright, who secured a 310-vote victory over Labour's Charles Clarke in May, thanks in part to votes from University of East Anglia students, insisted he had yet to make up his mind on how to vote when the tuition fees legislation was brought forward.

The NUS has put Mr Wright on a hit list of vulnerable MPs, accusing him of campaigning hard on opposing tuition fees in the run-up to the general election – at a time when his party was already considering dropping its opposition.

The NUS yesterday targeted Mr Wright through its Right to Recall campaign, hoping to make use of planned legislation which would mean MPs found guilty of wrongdoing would be vulnerable to a constituency petition. This would trigger an immediate by-election if 10pc of the electorate want it.

While that legislation has yet to be introduced and it is unclear whether it would be enforceable for a perceived broken promise, the NUS hoped it could be used to oust Mr Wright, along with deputy prime minister Nick Clegg from Sheffield Hallam, Stephen Williams in Bristol West and Don Foster in Bath.

But Mr Wright said: 'I still haven't made a decision on how to vote because it is terribly important to look at the evidence on both sides. It is not as straightforward as voting on an increase or not. There is a whole package of proposals.'

Some Lib Dems, including Sir Menzies Campbell, Charles Kennedy and newly elected party president Tim Farron, have already said they will openly oppose the government's proposal to increase annual fees.

The NUS plans to petition people in Norwich over whether they want Mr Wright to be subject to recall.

Meanwhile, two leading opponents of the government's plans for higher education will be at UEA tonight for a debate on tuition fees.

Adrian Ramsay, deputy leader of the Green Party, who finished fourth in the Norwich South election, will speak at the meeting alongside former Norwich North Labour MP Ian Gibson, who was a vocal opponent of variable tuition fees when they were introduced by his then constituency neighbour and education secretary Charles Clarke in 2005.

Norman Lamb's column - page 17.