IT IS the planning guideline intended to protect Oxford’s historic skyline.

It is even named after one of the city’s oldest towers.

But Oxford City Council’s own officers have decided to overrule their own principles to pave the way for a controversial new five-storey building.

They have suggested construction of the Blavatnik School of Government in the city centre may go ahead despite the fact it is more than four metres too high.

Under the so-called Carfax Guideline, buildings within 1,200m of the 23m high Carfax Tower are prevented from exceeding 18.2m. The proposed school of government in Walton Street is 22.5m high – 4.3m more.

Planning officers argue an exception should be made in a report to next week’s west area planning committee.

It says: “The design has evolved from a fundamental principle of creating a ‘forum’ within the building. Its shape is a deliberate expression of this principle.

“To reduce the height would compromise not only the requirements of the brief but also the sense of proportion between each floor and the composition as a whole. The building has a carefully calculated geometry.”

The report goes on to say that while the building will be visible from South Park and the hills west of Oxford, it would not be harmful to those views.

It comes during a row over Oxford University’s Castle Mill development, which campaigners claim ruins the views of the city’s “dreaming spires” from Port Meadow. The 17m-tall blocks of student housing were approved after the university lowered them by 1.2m.

Campaigner Sushila Dhall said: “When they made these rules the idea was to protect the views of Oxford and they seem to have thrown that away.”

Peter Thompson, the chairman of Oxford Civic Society, said: “We feel the applicants have not justified their design for the height.”

But city councillor Colin Cook, executive board member for city development, said there had already been exceptions, such as the 29.6m Said Business School spire.

He said: “If we had hard and fast rules we wouldn’t need planning committees to come to a decision because an application would either be in compliance or not.

“There are occasions when there are good reasons why we wouldn’t want to apply a rule absolutely rigidly.”

The building, on part of the former Radcliffe Infirmary site, has been created thanks to a £75m donation from billionaire Leonard Blavatnik and is designed by Herzog & de Meuron of Switzerland.

Currently based in Merton Street, in September the school – Europe’s first major school of government – welcomed its first intake of 39 postgraduates.

Calum Miller, chief operating officer, said: “We are pleased the report supports our view that this is a carefully considered and high quality building which is appropriate to its context.”

He said the actual height of the building was 22m – blaming the additional 50cm on a small balustrade at the top.

A decision will be made on Wednesday, May 8, at 6pm in Oxford’s Town Hall.