Concerns new school catchment areas will cause an increase in traffic and pollution have been played down ahead of a crucial meeting.

Campaigners opposed to the secondary admissions scheme in Brighton and Hove said dozens of parents would be forced to drive their children to school because the new catchments would stop them getting places within walking distance.

But Roger French, managing director of Brighton and Hove Bus and Coach Company, said he did not believe there would be a rise in road use as a result.

His sentiments were echoed by Keith Taylor, convenor of the city's Green group, who said many children would have shorter journeys to school because of the new system.

Mr French said: "Surely the principle of the catchments is to allay areas to schools. I would have thought that will mean less long journeys."

Mr French said parents would not need to drive their children because many school journeys were already catered for by existing bus routes.

He added special services funded by the council to take pupils to distant schools were to be reviewed in 2008, which meant they could be adapted to meet the needs of the new system.

Councillor Taylor said: "I cycled to school when I was a kid, I don't see what is stopping children now."

Members of Brighton and Hove City Council's children, families and schools committee agreed to introduce the catchment areas in a vote on February 2.

That decision will be reviewed by the children and young people's overview and scrutiny committee at Hove Town Hall at 5pm today after members of both the Labour and Conservative parties questioned the way it had been reached.

One of the key problems of the existing system is that some children cannot get into any of their nearest schools because they live too far away.

Places are allocated to children who live nearest to them. As a result, some pupils have been allocated places at schools at the opposite end of the city from their homes.

Some have to travel from west Hove to Falmer or Patcham high schools in the north-east of the city, while others go from Whitehawk in east Brighton to Hove Park school in west Hove.

Some parents argue the new catchment areas will mean children in Prestonville, Withdean and Westdene will have to travel almost four miles to Hove Park School when at present they can walk to Dorothy Stringer School.

The council's journey planner website shows a car journey from Sackville Gardens in Hove to Falmer High School in Lewes Road would produce 1.75kg in carbon emissions. A trip from Brigden Street in Prestonville to Hove Park lower school in Hangleton Way would cause emissions of 1.2kg.