Tusmore House in Oxfordshire — one of the winners of the 2004 Georgian Group Architectural Awards — is among several grand homes around the world owned by Mr Said, 65, who was born in Syria, holds Saudi citizenship but has chosen England as his home.

Mr Said has apartments in Eaton Square, London, on the Quai d’Orsay in Paris and houses in Marbella and Monaco.

He is a reluctant public figure with friends in high places from across the political spectrum. He is best-known for helping Baroness Thatcher secure the £20 billion al-Yamamah defence agreement between Britain and Saudi Arabia — a deal which led to him being labelled an arms broker.

Mr Said hates that description and prefers to be known for his extensive investment interests. His Said Holdings group has business interests around the world. The £30 million house stands on the site of one of Oxfordshire’s most lamen ted lost country houses, the Georgian Tusmore House which was demolished in 1961.

The new Tusmore was designed by 84-year-old Sir William Whitfield. It is entered via impressive gates leading into a vast walled park where the house is set commandingly on rising ground looking down to a lake. The entrance is dominated by a monumental portico with six giant Ionic columns.

Sir William has banked up the ground on the approach so there are only three shallow steps to the front door. On the other three sides the ground falls away to reveal a ground floor with French windows opening on to the garden.

The interior is laid out around a grand staircase set in a rotunda with a top-lit dome supported on a ring of polished columns made from imitation marble. The staircase, with its twin flights, is modelled on a similar one at 18th century Wardour Castle in Wiltshire.

Among other designs considered by Mr Said were those submitted by the late Philip Jebb — who proposed an exact replica of the original 1770 design — and the leading classicists Quinlan Terry and Julian Bicknell.

For years visitors have been disappointed by the weak classical replacement, built in 1964, which was puny in scale and jarring in colour compared to the handsome surviving stables and outbuildings. It had been designed by the fashionable country house architect, Claud Phillimore.

Mr Said’s Tusmore is built of white stone. Sir William imported stone from Dijon in Burgundy as sufficient supplies could not be found in Oxfordshire.

The triumphant classicism of the design is in complete contrast to the Government’s recent call for new country houses to have a cutting-edge innovative quality.

However, Mr Said cannot be accused of living in the past — the Oxford business school which bears his name is a sleek, modern building from the architects Dixon and Jones.

www.timesonline.co.uk/property

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