FOR the Blairs, the sun is setting over Downing Street, but two miles away a £3.65m townhouse in an area known as “Little Beirut” is being prepared for a new dawn.

The Blairs are equipping their retirement home with a rooftop sun terrace to enjoy their new-found freedom, and four solar panels as a nod to fashionable green orthodoxy.

While it may lack the pulling power of an invitation to Downing Street or Chequers, the family’s glitzy friends — past guests have included Delia Smith, Kirsty Young and Sir Elton John — can still expect a house well equipped for a party.

The renovation programme, laid out in documents lodged with Westminster city council, may force the family to find alternative accommodation if, as expected, the handover of the premiership to Gordon Brown takes place in late June or early July.

However, it will be worth the wait. If the plans are agreed, the house, whose interior has previously been pilloried as drab, ugly and “a disgrace”, will be transformed.

The terrace is to be built two stories up, in a sun trap between the main townhouse and an adjoining mews, with views across the rooftops towards Hyde Park to the south.

The ground floor of the mews will be used for a sprawling kitchen, perfect for cosy meals with old family friends. It is here that Carole Caplin, a lifestyle adviser, may hope to be be welcomed back into the intimacy she once enjoyed with the family.

The grandest rooms in the Blair home will, of course, be those facing Connaught Square on the ground floor and first floor. The former prime minister may find himself here reciprocating the hospitality that enlivened the Downing Street years: from Sir Cliff Richard, who provided the Caribbean holidays, to Prince Girolamo Strozzi, scion of one of Italy’s oldest noble dynasties who helped nurture the family’s appreciation of Tuscany.

The addition of the mews house will help to solve the security risks of the main property, whose only entrance opens on to a public street. The mews opens onto a narrow rear street which could be blocked off.

The Blairs bought the main house, a grade 2 listed five-storey property close to Marble Arch and Edgware Road, in September 2004. They rented it to Michael Caton-Jones, the film director, who stayed there while making Basic Instinct II. The mews reportedly cost £800,000 last month.

It is close to some of London’s busiest roads, including Marble Arch. Nearby Edgware Road is a centre for London’s Arab community, with numerous cafes and restaurants.

In a recent television drama, The Trial of Tony Blair, the actress playing Cherie Blair dubbed the area Little Beirut, adding: “Not a great place to live when your husband is hated by 250m Arabs.” Lord St John of Fawsley, the former Tory minister, has claimed that when he looked at the house with a view to buying it three decades ago, he found the body of a tramp in the cellar.

The plans to turn the two houses into one — which could easily cost £100,000 — are filed under the name of Simon Templeton, an architect who is the most recent owner of the mews house, 5 Archery Close, according to official records.

The alterations would need to be completed quickly if Blair is to move in after handing the premiership to Brown.

The plans show that two new CCTV cameras would be installed on the external front walls of the main house. Security experts believe the house would be fitted with panic alarms and motion detectors.

Rumours are circulating among Connaught Square’s residents that nonresidents will be barred from driving though the square. One employee at the Connaught Square Practice said: “[I’ve heard] part of the square will be closed off.”

Westminster council said it was unaware of any plans for such a scheme.

The cost of protecting Blair will be met by the taxpayer: the annual cost of 24-hour protection for Sir John Major, his predecessor, has been put at more than £1.5m.

The purchase of the mews house brings the number of homes that the Blairs own to five. They include Myrobella, the Co Durham home that Blair bought for £30,000 in 1983, and two flats in Bristol, bought at a combined cost of £525,000 in 2002.

The Blairs’ total mortgage debts have been calculated at £4.7m but the prime minister is expected to earn millions from book deals, company directorships and the lecture circuit when he leaves office.

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