The SNP made several election pledges to boost education

The plea came as Scots Lib Dem leader Nicol Stephen said the government had failed to put forward detailed proposals on achieving the goal.

The SNP pledged to cut class sizes to 18 for the first three years of primary school during the election.

But Mr Stephen questioned whether this would be a "long term" objective, as with plans to upgrade the A9 road.

Speaking during First Minister's Question Time, Mr Salmond said a class size announcement would come within weeks.

'Vital initiatives'

Mr Stephen demanded to know the government's target date for delivering on that goal, how many extra teachers would be recruited and how many new classrooms will be needed.

"The Liberal Democrats are committed to reducing class sizes in Scotland with fully costed, detailed proposals to recruit 1,000 extra teachers and build 250 new schools," he said.

Mr Salmond urged the Lib Dems to work with him to help cut sizes in primaries one to three.

He also set out plans to increase free nursery education for three and four-year-olds by 50% and bring in a �10m fund to help youngsters with learning difficulties.