The Conservatives revealed figures showing 1,500 suspensions of children aged four and under in the past year.

In response, heads’ leader Mick Brookes says it reflects teachers’ fears that they could lose their jobs if they intervene to stop violent pupils.

As such teachers are using suspension powers instead, says Mr Brookes.

Teachers were worried by a culture of litigation and the fear of unjust accusations, said Mr Brookes, and as such they opted to use procedures to exclude violent toddlers.

‘Shocking’

"The culture we have in our schools now means that every time they lay hands on a child to restrain them from hurting themselves or others, they put their jobs on the line," said Mr Brookes, general secretary of the National Association of Head Teachers.

"You would be surprised by the vehement language and the violence that comes in with very young children these days, it’s quite shocking," Mr Brookes told BBC Radio 4’s Today programme.

The figures obtained by the Conservatives showed 580 fixed-term exclusions of five-year-olds, 300 of children aged four and 120 of those aged three, for attacking another pupil, data shows.

There has been a steady rise in temporary exclusions at primary schools, while permanent exclusions have fallen.

Primary school permanent exclusions - published in June - were down to 980 compared with 1,540 in 1997.

There were 45,730 fixed term exclusions (suspensions) in 2006/7, compared with 43,720 in 2004/5 and 41,300 the year before.

This is the first year that the government has given a breakdown of the reasons for suspensions among various ages of primary school children.

The data shows there were 890 exclusions of five-year-olds for assaulting an adult, along with 420 of four-year-olds and 140 of three-year-olds.

In total, there were more than 4,000 fixed-period exclusions handed to children aged five and under.

The figure for those aged four and under is 1,540, the majority of whom were four (1,140).

The exclusions relate to a very small proportion of the primary school population.

Disruptive

For example, in the case of children aged four who were suspended, if it is assumed the figure of 1,140 relates to individual children, it represents about 0.2% of the pupils in that age group in England’s schools.

The data showed that there were 10 suspensions of five-year-olds for bullying, and a further 20 for sexual misconduct.

But there were 1,000 suspensions of under-fives for persistent disruptive behaviour.

The statistics were obtained through a parliamentary question by shadow schools secretary Michael Gove.

"Teachers need the powers to maintain order in the classroom and clamp down on bad behaviour before it escalates into violence," said Mr Gove.

"Ministers have eroded teachers’ ability to keep order by restricting their powers to deal with disruptive and violent children."

The government insists schools do have the power to take action against children behaving badly - and that this data shows they are doing so.

Heads’ powers

A DCSF spokesman said: "It is very difficult to see what argument is actually being presented here. Of course heads have the power to permanently exclude pupils where necessary but we are also helping schools to turn around poor behaviour before it reaches this stage

"Violence in the classroom, at any age, is not acceptable and teachers have the power to take appropriate action against young children involved in such acts - and these figures show that they are doing that.

"It’s important to remember though that behaviour in the vast majority of schools is good most of the time and a recent survey of teachers showed that around nine in 10 felt that behaviour in their school was satisfactory or better."

The schools system in England is failing poorer children "at every turn", says the Shadow Schools Secretary, Michael Gove.

He says initiatives to close social inequalities in exam results and staying on rates are not succeeding.

But the Conservatives say they have no plans to scrap the maintenance allowance to keep youngsters in school.

Schools Minister Jim Knight says that "Tory policies would simply preserve excellence for the few".

Mr Gove’s speech asserted his party’s commitment to strengthening family life, promoting responsible fatherhood and supporting children from the most deprived backgrounds.

‘Opportunity gap’

"Schools should be engines of social mobility, the places where inherited disadvantages are overcome and individual talents can be nurtured to make opportunity more equal," Mr Gove told the IPPR think tank.

"But the record of this government has been of inequality growing, and the opportunity gap widening, between the fortunate and the forgotten.

"In the last year for which we have figures the gap at GCSE between the performance of students in the 10% of wealthiest areas and the 10% of poorest areas doubled."

Mr Gove’s speech highlighted the lack of success for pupils on free school meals at the basic level and among the high-flyers.

He warned that 47% of such poorer pupils did not achieve a single GCSE at grade C - and that only 176 pupils eligible for free school meals had achieved three A grades at A-level - less than 1% of the total.

The Conservatives have also argued that there has been too little progress in poorer pupils staying on at school beyond the age of 16, despite the introduction of the education maintenance allowance (EMA).

But a party spokesman said that there were no plans to stop the EMA, which gives financial support to keep youngsters in education.

Mr Gove also spoke of his support for the Sure Start scheme to help families with young children.

Deadline

Schools Minister Jim Knight rejected the claims that the government is failing to tackle the achievement gap between rich and poor pupils.

He pointed to the current "National Challenge" which has set a deadline to ensure that all secondary schools in England, including those serving the most deprived areas, achieve at least 30% of pupils getting five good CGSEs.

Individual catch-up lessons in reading, writing and maths, the forthcoming Diplomas and raising the leaving age to 18 would all be steps to supporting children from poorer backgrounds, he said.

"If the Tories were serious about improving outcomes for the poorest children, they would support our plans to strengthen local children’s trusts, drop their pledge to cut funding to Sure Start and finally commit themselves to our ambitious targets on child poverty."