Campaigners have won a significant victory in their battle for a new primary school in Bristol.

The Liberal Democrats, who took control of the city council last week after the minority Labour administration resigned, today announced a move to revert to the plan to build a new school in Bishopston, rather than expand at Sefton Park.

They say they want to see the new primary open by September 2010 on a site close to City of Bristol College's Ashley Down campus.

The news will be welcomed by two groups of parents in the area, which is chronically short of school places for children aged four to 11.

They are the families of children already at Sefton Park, who say the site is already overcrowded as a two-form entry school and cannot cope with taking a total of 630 primary pupils plus nursery children, and the families whose children are due to start in September and do not yet have a place at any school.

The two groups, Agro (Ashley Grange Residents Organisation) and BPAC (Bristol Primary Admissions Crisis), will be discussing the new developments shortly.

Sefton Park's governors were told of the proposals yesterday and issued a statement to parents which said: "The local authority has decided not to expand Sefton Park Schools at this time. Instead a recommendation for the building of a single form entry school on the Brunel site, planned to open in September 2010, will be presented to cabinet."

The statement said the governors would now consider the council's request for a third reception class for September 2009 to help meet the demand for places.

Chairwoman of governors Janet Bremner said: "In particular, we are awaiting a formal response to the issues we raised with them (the local authority) in relation to the physical capacity of the school site and the budget implications of a second three-form year group."

The Liberal Democrats gave the go-ahead for a 210-place primary on the college site, known locally as the Brunel field, when they were last in charge at the Council House in 2007.

But Labour reversed the decision in January 2008, opting instead for a £6.9 milion scheme to refurbish and expand Sefton Park infant and junior schools.

Many of the parents believe the U-turn was prompted by the intervention of Gloucestershire County Cricket Club, which was concerned that having a school on the college site- known as the Brunel field – would threaten its ability to stage big matches.

But the council said the reason for the change of policy was that it no longer favoured building single-form entry schools.