THE stepson of Narnia creator CS Lewis has added his opposition to plans for an extension at the church where the writer is buried.

Plans for the extension at Grade II-listed Holy Trinity Church in Headington Quarry were backed by former vicar Tim Stead.

The new building is designed to house a disabled toilet, crèche and kitchenette but some members of the congregation are bitterly opposed to the plans and the Holy Trinity Preservation Group said the scheme should be abandoned.

Now the fantasy author’s stepson Douglas Gresham has added his opposition in strongly-worded letters to the parochial church council.

He said the ‘abominable’ extension should not be permitted, despite Rev Alexander McGregor of the Consistory Court of the Oxford Diocese deciding that it should go ahead.

Mr Gresham, who lives in Malta, wrote: “I and many others are both disappointed and alarmed at the plans that have emerged from some damaged mind to desecrate a long area of the lovely churchyard of Holy Trinity Church Headington Quarry.

“You should also bear in mind that people come from all over the world to visit the church and especially in many cases to see the beautiful Narnia Window, which was donated by a bereaved family and which the silly additions will cover.

“Many times in my life I have seen lovely buildings ruined by unnecessary additions which always seem to me to stem from the minds of egocentric people seeking to enlarge their fiefdoms.”

In a ruling last month, Rev McGregor noted that planning permission had been granted for the extension – by Oxford City Council – and added that the current facilities offered by the church were ‘deficient’.

He added that the church required ‘decent facilities for a kitchen, a creche/ meeting room, a vestry and an accessible lavatory on site’.

The reverend, referred to as Chancellor of the Consistory Court, said objections regarding the setting for the memorial window did not ‘carry any weight’.

But Jenifer Carpenter, chairwoman of the preservation group, said the fight was not yet over, despite the ruling, and she welcomed Mr Gresham’s intervention.

She added that the extension could cost £500,000.

Narnia author CS Lewis, who died in 1963, is buried in the churchyard but his grave would not be affected by the plans.

The extension site directly affects one grave, that of Cyril Frederick Coppock who was buried in 1975 and was an ex-serviceman in the First World War, along with his wife Florence, buried in 1980.

Rev Stead was vicar at the church for 10 years until he left in April to work freelance.