Secondary maths can be expected to get harder under the new curriculum, a senior civil servant has warned.
The national curriculum is currently being reviewed and a new one is likely to be in place by September 2013.
Jon Coles, director general for education standards at the Department for Education, told a conference last week that standards in primary maths held up when compared to other high-performing countries. But he added that results did not appear to compare so well at secondary level, and more of a "challenge" might be needed.
Speaking at the Advisory Committee on Mathematics Education conference, Mr Coles said: "This (curriculum review) is a very serious attempt to examine in very precise detail what is actually happening in the classrooms of other countries that are outperforming us, and to learn from that evidence.
"At secondary level, I think we will see an upping of the challenge and expectation." He added that it was too early to say what this would mean for GCSEs.
"We cannot fully reform GCSEs until we have fully implemented the new national curriculum," he said. "We can't rush this. We have to make sure that schools have adequate time to prepare, particularly if there is greater demand in the curriculum."
While the number of students achieving a C in GCSE maths and those going on to do A-levels and degrees in the subject has increased in the past 10 years, the latest international study from Pisa (the Programme for International Student Assessment) found that 15-year-olds in Shanghai were more than two years ahead of students in England.
Jane Imrie, deputy director of the National Centre for Excellence in the Teaching of Mathematics, said: "I think the challenge is already there in the curriculum: the issue is how we get it into the classroom. We need to allow that challenge to happen and that may be about the way we assess maths.
"It's not as simple as saying 'now do calculus at GCSE rather than AS-level'. It is not about putting harder content in because the more content there is, the more time you spend on technique and not on using maths.
"It would be like spending all your music lessons learning harder and harder scales and arpeggios but never playing a piece of music."
The conference also heard that the evidence for primary maths pointed towards covering fewer areas in more depth.
Tim Oates, who chairs the panel of experts overseeing the curriculum review, told the conference it was becoming clear that some high-performing countries covered fewer things in greater detail at primary - which then led to a much more dense secondary curriculum.
He added: "In response to those people saying there is rather naive cherry-picking from other systems going on, I want to reassure them that this is absolutely not the case. There is considerable sophistication in the approaches that are being adopted within the review in terms of transnational comparisons."
The review of the national curriculum is open for submissions until 14 April.
'It is thrilling'
Maths teaching has experienced a popularity boost this year, with more than 33 per cent of those inquiring about teaching considering a maths specialism.
The figure is up from 26 per cent in 2010, the Training and Development Agency for Schools (TDA) telephone information line poll shows.
It reveals that in London, 36 per cent of those considering teaching favoured maths and 45 per cent were considering changing career to teach the subject.
TDA chief executive Graham Holley said: "It is thrilling to see maths teaching enjoying such a renaissance. We are determined to capitalise on the increasing interest ... to ensure future economic prosperity."