By Gary Eason
BBC News Online education editor, in Llandudno
Conservative plans to stop schools giving admissions priority to pupils who live nearest would be phased in gradually, a party education spokesman has now said.
Tim Collins wants the attainment 'gap' between schools closed
Tim Collins said scrapping the so-called "proximity rule" would not come with a "big bang" the day after the party returned to government.
It would depend on driving up standards in all the schools in an area, so parents had more choice and were not all fighting for places in one or two popular schools.
Education Secretary Charles Clarke says the Tories are in "total chaos".
On Sunday, the shadow education secretary, Tim Yeo, had said it was unfair that affluent parents could take places at good schools by buying houses nearby.
"We aim to give to the many the privileges now only bought by a few," he said.
Explaining the party's "pupil passport" scheme, he said: "The whole essence of this policy is that we no longer want schools in expensive areas to exclude people from poor areas merely because they don't live nearby."
He confirmed this would mean abolishing the proximity rule.
Parents can already in theory apply to more or less any school for a place for their child.
But popular, heavily over-subscribed schools typically allocate places by giving priority to those living nearest, as well as other criteria such as whether a brother or sister is at the school.
Mr Collins, speaking to journalists at the NASUWT union's annual conference, in Llandudno, on Thursday, said: "We have to move over a period - we are not talking about a big bang the day after we come to office.
"We are talking about a general levelling up of standards."
"At the moment," he said, "there's a big gap between the very best state schools and the very worst state schools.
"We want to make sure that our policies close that gap, give every parent the choice of getting their child into an excellent school.
"If we do that we will be able to, alongside that, to move away from having a rule that schools simply admit on the basis of those that live in the nearest streets."
What is still not clear is how schools would choose if they were over-subscribed but could not do so on proximity.
But Mr Collins ruled out any idea of a widespread return to selection by ability.
"It's not my view that it's helpful for us, going forward into the 21st century, to re-run the debates of the middle of the 20th century about whether we should have selective education or not.
"Most of those decisions were taken before I was at primary school."
He added: "We don't have an agenda, either closed or open, to reintroduce selection by ability."
Education Secretary Charles Clarke accused the Conservatives of being in disarray over education.
"The Tories are in total chaos. Tim
Collins is now backtracking on Tim Yeo's announcement on Sunday," he said.
"This is now a pattern of Tory education policy - admissions policy is now
following the same fate as the school passport policy.
"We are still waiting for clarification of their vocational policy, their
higher education policy, school passports and now admissions.
"It is clear that the Tories have no idea where they are going or what they
are doing in education."
The Secondary Heads Association say people need a clearer idea of the Conservatives' intentions on school catchment areas.
General secretary John Dunford said: "Over-subscribed schools have to use criteria to decide who to admit and if
catchment areas or distance from school are not used, then inevitably academic
selection will expand.
"This will cause greatly increased anxiety for many parents and pupils and
organisational difficulties for schools.
"No amount of phasing in can hide these facts."