The Liberal Democrats have stepped up their election campaign, pledging a big increase in the number of teachers.

Charles Kennedy said his party would deliver 21,000 extra teachers for five to 11-year-olds.

This would mean primary school children benefiting from more individual teacher time, said the party.

Kennedy said he was determined to to deliver "high quality education for our children".

"Education is the key to so many of the opportunities that our society offers. And it is the best investment that our generation can make on behalf of the next," he said.

"Every parent of young children wishes they could spend more one-to-one time with them.

"That's sometimes difficult in today's hectic lives.

"So giving teachers more time to spend with every child will help give children a flying start; so that they can bring out the best in them - so they can inspire our children to learn and to be ambitious."

Costs

The cost of employing and training 21,000 teachers over the course of the next parliament is put at £1.165bn.

This would be funded by scrapping the government's child trust funds, which cost £1.5bn.

The additional teachers would mean class sizes for infants being reduced from 25 to 20.

And in junior schools class sizes would fall from 27 to an average of 25.

Critics have said that many schools will lack the physical space to provide the extra classes, but Lib Dem education spokesman Phil Willis insisted the policy would benefit those who need the most help.

"Instead of a cash hand out for 18-year-olds from a child trust fund that favours those whose parents can already afford to save for them we will spend the money reducing class sizes, a measure which benefits all children regardless of their parents wealth or background," he said.

"Smaller class sizes create a better learning environment and help foster better behaviour within the classroom."

Key seats

Later on Monday, Kennedy was stepping up his election campaigning, visiting key constituencies in Surrey and Devon.

He was set to visit the South West Surrey constituency with his party's candidate Simon Cordon.

The seat was held for the Conservatives at the last election by former Cabinet minister Virginia Bottomley.

She beat Cordon, who also stood in the seat in 2001, with a wafer-thin majority of just 861.

In the afternoon, Kennedy travels on to campaign in Totnes.

It is also a seat where the Lib Dems are in second place to the Conservatives, though this time Michael Howard's troops are defending a majority of 3,597.

The seat saw a closer result in 1997, however, when the Lib Dems trailed the Tories by just 877.