Inspectors have condemned one of Tony Blair's multi-million pound city academies, 12 months after it became the first of the flagship schools to be failed by Ofsted.

Truancy, poor teaching, inappropriate buildings, and "exceptionally low" results meant Unity City Academy, in Middlesbrough, had made "inadequate progress" since last March, inspectors said.

Under the Prime Minister's education reforms, failing schools which do not improve within a year will face being closed down - and replaced by a city academy.

The school's new chief executive David Triggs - brought in by the Department for Education - said such a 12-month deadline would be virtually impossible for schools in Unity's position.

"Whilst I can understand the Government wishing to get tougher - and rightly so - every school has a different context," Mr Triggs said.

"Schools like Unity are in very challenging circumstances. You have to be realistic. To turn a school like that round in 12 months is, I believe, nigh-on impossible."

Sponsored by business support services firm Amey, Unity opened in 2002 and teaches about 1,200 11-16 year-olds. The latest damning judgment came in a letter from inspectors to Mr Triggs, who has a track record of turning round failing schools.

The inspectors found:

* Pupils make "exceptionally low" progress between the ages of 11 and 14, with English and science results among the lowest in England;

* Children from poor backgrounds scored particularly low results;

* Only six per cent of teenagers got at least five C grades at GCSE in subjects including English and maths;

* Even most of the brightest pupils made no real progress in the first few years of school, while an unusually large proportion of teenagers failed to pass any GCSEs at all.

The report said behaviour had improved and was now satisfactory, with the number of students excluded from school down significantly. But overall progress on improving pupils' attitudes, behaviour and attendance was inadequate. Some pupils are too boisterous while supply teachers fail to keep control in lessons and loud behaviour during break times goes unchecked.

The inspectors were particularly critical of the academy's new buildings, which are designed with a series of balconies and intended to look like an Italian hill village.

They said: "The nature of the building, while impressive at first sight, means that some students do not feel safe or secure. The layout of corridors is confusing and high, open balconies and stairwells are daunting."

The inspectors said there were signs that improvements had been made, particularly in areas such as behaviour, pupils' self-esteem and the school's leadership.

The Government admitted that there was "much work to be done" to turn the academy around but stressed recent action was beginning to have a positive effect. Asked if the school would be closed if it continued to make inadequate progress, an Education Department spokesman said ministers wanted the academy to improve "quickly"