Education secretary Michael Gove was last night facing a major backlash from teachers and politicians over his controversial plans to bring back O-levels.

Headteachers in East Anglia voiced fears that ditching GCSEs in favour of O-levels and CSEs would create a classroom divide and risk branding teenagers as failures - while Liberal Democrat leaders attacked the idea and even Downing Street declined to say whether David Cameron approved of Mr Gove's proposals, or actually knew of them in advance.

Leaked plans of Mr Gove's intentions to overhaul the exams system and abolish the national curriculum from September 2014 emerged in a national newspaper yesterday.

Education leaders warned they would bring back bad memories of 1980s' education when students were made to 'feel like failures' if asked to study the easier CSEs instead of the tougher O-levels.

The timing of the leak has also been regarded as insensitive, with thousands of pupils preparing to sit their GCSEs.

Victoria Musgrave, Wymondham High School principal, said she felt 'extremely sad' as many people still 'bear the scars' of the split caused by O-levels and CSEs.

She said: 'It seems to me that this would be a retrograde step. What useful purpose will it serve? Mr Gove talks about raising standards and we in schools know that this has been our focus over many years and every time we do what we are bidden, the press have a field day stating 'examinations are getting easier' and headlines like 'dumbing down', rather than commenting on how hard both students and staff are working.'

Rob Anthony, senior associate headteacher of the Hewett School, Norwich, said it was 'right and proper' to review the ways examinations were done - but in a sensible manner with proper consultation.

He said: 'It's reported we are going back to O-levels and CSEs. I remember them as a young person and people doing CSEs felt like they were failures and not worthy of O-levels.

'I am concerned about some aspects while some things are great. I like the idea of getting rid of a national curriculum and freeing things up. That's a positive.'

Earlier yesterday Mr Gove was hauled before the Commons to answer an urgent question on the shake-up.

Defending his plans, he said: 'The truth is we have a two-tier system in education in this country. Some of the most impressive schools have already left GCSEs behind and opted for more rigorous qualifications like IGCSEs.

'While there were undoubtedly improvements in our schools and by our teachers over the course of the last 20 years, those improvements were not sufficient to ensure that we kept pace with other jurisdictions.''

Conservative MP Graham Stuart, chairman of the cross-party education select committee, said he was sceptical about the proposals which had come 'out of the blue''.

The Lib Dems dismissed the plan as a return to the 'two-tier' system of the 1950s, saying no one outside of Tory Cabinet minister Mr Gove's office appeared to have known it was being considered. 'Nick Clegg and the Lib Dems do not want to return to the divisions we saw in the 1950s,' a source said.

Norman Lamb, North Norfolk LibDem MP, said: 'I'm yet to see the detail of these proposals but I do favour exacting standards. Whatever means you use to getting strong qualifications that are recognised by universities is ok, but high standards are the important thing.'

Meanwhile a No 10 spokesman said: 'The Prime Minister entirely agrees with the Education Secretary that we need to raise standards. It is the Education Secretary's job to look at the detail.'