The headteacher of a free school told it will not be able to open until 2015 has urged parents to "put pressure" on the Department of Education to change its mind.

Harperbury Free School was set to move into the Postgraduate Centre at the former Harperbury Hospital in Harpers Lane in Radlett this September while a permanent site was being prepared.

Formerly used for training nurses, the building recently became empty and governors concluded it would be ideal as a temporary home for the school.

A permanent site for the free school in Harperbury Hospital was identified 18 months ago; however the Department of Education is still negotiating with its owners the Department of Health to secure it.

And under a new rule introduced by School’s Minister Lord Nash, the school cannot open the temporary site until the permanent one has been secured.

This means the school’s opening will now be delayed until 2015.

Headteacher Martin Blain said everyone had been left “in limbo” by the decision.

He said: “We are very disappointed indeed he has left it so late to tell us there were problems with the permanent site. Up until January we thought everything was on track, we thought it was a done deal.

“We had everything ready to open in September. We had done everything the Department of Education asked us to and they kept saying we were a perfect project, and now they tell us when there is no room to do anything about it.

“They’ve failed to do the one thing expected of them, which is to find a permanent site for us.

"They have treated us really badly; we have done nothing to deserve this.”

Mr Blain, who had left his job as deputy headteacher at Immanuel College in Bushey to work on the project full-time, said he “felt terrible” for all the parents who were preparing to send their children to the school in September.

He said: “This not a position we ever thought we’d be in. We were just about to send acceptance letters out to pupils, and now we have had to let them down in this way. I spent so much time persuading parents to trust us with their children and now they will have to send them to other schools.”

Mr Blain said the rule about not moving into a temporary site until a permanent one was found had only recently thought up by Lord Nash and asked why he could not bend it.

He added: “There is no economic or political reason for this rule, just a piece of crazy admin.

“We’re hoping if enough parents write in and say how outraged they are about Lord Nash’s decision, and if people from the area make a big fuss and put pressure on him he might decide to change his own rule and go ahead for 2014.”

In the meantime the school is discussing opening a Year 8 class so the children who missed out this year can have a second chance.