Media playback is unsupported on your device Media caption Nick Clegg asks students to call off planned tuition fee demonstrations

Liberal Democrat leader Nick Clegg is calling on students to reconsider the coalition's tuition fees plans before they take part in a day of protests.

"Examine our proposals before taking to the streets. Listen and look before you march and shout," says Mr Clegg.

Students are planning protests against tuition fees and budget cuts in London and across the UK on Wednesday.

A student protest two weeks ago resulted in an attack on the Conservatives' headquarters building.

Further education college students and school pupils are also expected to join students in walkouts, rallies and occupations.

The Metropolitan Police have warned they will not tolerate criminal activity, violence or disorder.

On Tuesday, students demonstrated while Mr Clegg made a speech promising that the coalition government plans for tuition fees would "make higher education open to everyone".

The Liberal Democrats have become a particular target for student protests.

Students have accused Liberal Democrat MPs of planning to break their pledge to vote against raising fees - and a demonstration is planned for Wednesday outside the party's headquarters.

Here's what makes me angry. Oxford and Cambridge take more students each year from just two schools - Eton and Westminster - than from among the 80,000 pupils who are eligible for free school meals Nick Clegg

Under the government proposal now being backed by Mr Clegg, the level of tuition fees at English universities would increase almost threefold to up to £9,000 - and public funding for university teaching budgets would be reduced for many subjects.

Mr Clegg told his audience that, under the new plans, many of the lowest income graduates would repay less than they do under the current system.

"Nobody will pay a penny back until their earnings reach £21,000 per year, compared to £15,000 now. The highest-earning graduates will pay back the most."

Protests planned

Protests are planned around the country in what demonstrators are calling "Day X".

Mark Bergfeld, spokesman for the Education Activist Network, said: "We have the right to protest, we have the right to civil disobedience, we have the right to occupy our lecture halls."

After the attack on the Millbank office complex at the last march against raising tuition fees, there is expected to be a much more visible police presence.

Protesters in London are planning to gather in Trafalgar Square and then stage demonstrations outside the Liberal Democrat headquarters and Downing Street.

Students aim to deliver a letter to Lib Dem leader Nick Clegg with the message: "You have lied to us."

The demonstrations on Wednesday are not being organised by the National Union of Students - and there are uncertainties about the pattern of protests.

A "carnival of resistance" has been promised, with music and speeches.

But an anarchist group has also called for "roaming marches" to "disrupt business" across central London, rather than a static stand-off with police.

'Wave of revolt'

Protest leaders have claimed that an "unprecedented wave of student revolt is unfolding" - and they say they are following in the spirit of student protests of 1968.

Image caption Students have directed much of their anger at the Liberal Democrats

There have been three occupations in universities this week - and there are plans for events in many university cities.

There are protests planned in cities including Birmingham, Manchester, Liverpool, Bristol, Southampton, Leeds, Newcastle, Cardiff, Glasgow and Edinburgh.

As well as the planned rise in tuition fees, students are also campaigning about wider funding issues.

The spending cuts will mean that government funding for university teaching budgets will be withdrawn from many subjects, particularly in the arts and humanities.

Further education students and sixth-formers are also protesting at plans to remove the education maintenance allowance, which gives low income students up to £30 a week to help with the costs of staying in full-time education.

The fees protest held two weeks ago in Westminster was attended by an estimated 50,000 students - and ended with a breakaway group forcing their way into the Millbank office complex.

There had only been a thin line of police guarding the Millbank building - but the police have made clear that they will be better prepared for Wednesday's protests.

"The Met has long respected and protected the right to protest and we will continue to do so, but anyone who plans to take to the streets of London intent on disorder, violence and crime should understand that it won't be tolerated and they will be arrested," said Commander Bob Broadhurst.

Image caption At the election, Mr Clegg signed a pledge to students that he would vote against any fee increase

National Union of Students president Aaron Porter said: "Students looked and listened when the Liberal Democrats said that they were going to abolish tuition fees, at the time of the general election.

"Tens of thousands of students voted for the Liberal Democrats on that basis. We are still looking and listening for when the Liberal Democrats are going to stick to their promise.

"I think they would be well served to show a little humility and suggest why they have let down so many students."