Experts are called back in to fix Boris Johnson’s costly Downing Street decor

After being given a pasting for getting Tory donors to pay for gold wallpaper in his Downing Street flat, Boris Johnson faced fresh embarrassment last night – it keeps falling down.

The Prime Minister has had to call in specialist decorators to rehang parts of the £840 per roll ‘hand-crafted’ wallpaper, No 10 sources say.

The latest twist in the ‘Wallpapergate’ affair came as a photograph emerged of upmarket interior designer Lulu Lytle visiting Downing Street. The Daily Mail can also reveal some of the fabrics Miss Lytle’s Soane Britain company used in the refit of Mr Johnson and fiancee Carrie Symonds‘s 11 Downing Street apartment.

The sofa is upholstered with ruby and emerald material called Damascus Stripe. Miss Lytle says it is ‘based on a 19th century Syrian original pattern woven from cotton and silk’.

The curtains are thought to be Soane Britain’s Tendril Vine pattern, also in emerald. Appropriately for passionate eco campaigner Miss Symonds, who oversaw the revamp, the window frames and other parts of the woodwork are painted in a matching pastel green.

An enchanting photograph of Miss Symonds with Wilfred – her one-year-old son with Mr Johnson – was released by Downing Street at Christmas. At the time no one realised it had been taken in the No 11 flat – and the dispute over new decor for the apartment and how it was paid for did not erupt until it was revealed by this newspaper in February.

Mr Johnson’s newly appointed independent adviser on ministers’ interests, Lord Geidt, is carrying out an investigation into the way that the Tories tried to disguise a £58,000 payment for the refit from Conservative Party funds.

The problem with the wallpaper is thought to derive from the heavyweight paper used by Miss Lytle, who does not employ the production-line methods used for most domestic wallpapers.

Her website proclaims that her wallpapers are ‘made in British mills and workshops, employing traditional methods such as block screen printing’. She says it is worth it to ‘create high-quality modern wallpapers that capture the atmosphere of hand-crafted products’. Hanging heavy duty wallpaper is much more difficult than cheaper, lighter mass produced versions sold in most high street furnishing stores. As the cost of the makeover soared last year, the Prime Minister was heard railing that Miss Symonds was ‘buying gold wallpaper… I can’t afford it’.

Only now has it emerged that it was not another of Mr Johnson’s colourful euphemisms – the wallpaper actually is gold coloured.

Miss Lytle markets two such heavyweight patterned wallpapers, Old Gold and Yellow Gold. The vivid Damascus Stripe fabric used on the sofa – where Miss Symonds posed cradling Wilfred – is one of Miss Lytle’s most popular designs. Miss Lytle says her use of colours such as ‘raspberry and emerald is largely drawn from the Eastern Mediterranean and North Africa’.

They are inspired by ‘myriad sources, whether an oriental painting or overseas expedition’ and intended to be ‘joyful and uplifting’.

Tendril Vine is made of stone linen and described on the Soane Britain website as the company’s ‘first botanical print, a simplified interpretation of the incredibly intricate pattern on an early 19th century English fabric’.

Soane Britain recommends a similar Osmunda Frond green fabric as a ‘complementary piece’ to the Damascus Stripe. Miss Lytle defends her use of a fusion of exotic colours and styles, saying: ‘As a child I was exposed to lots of pattern – all our bedrooms were wallpapered – and colour.

‘My mother once remarked, ‘Raspberry’s just a neutral’ and used many deep pinks around the home.’ Miss Lytle added she was ‘dazzled by the glorious jewel colours’ at markets in Egypt.

Lord Geidt, former private secretary to the Queen, the Prime Minister’s independent adviser on ministerial ethics, plans to release the long overdue register of ministerial interests by the end of this month. He has said he expects Mr Johnson’s entry covering the renovation of his No 11 apartment, and his own advice on the issue, would be released as part of it.

In addition, the Electoral Commission announced three weeks ago that it is carrying out a formal investigation into the matter. The watchdog said it was ‘satisfied that there are reasonable grounds to suspect that an offence or offences may have occurred’.

The Commission has sweeping powers to demand documents and interview witnesses under caution. Failure to declare donations is an offence under electoral law, punishable by fines of up to £20,000.

Failure to comply or tell the truth is a criminal offence. The Commission can pass on investigations to the police if it uncovers evidence of criminal offences or believes its efforts are being frustrated.

Downing Street says Mr Johnson is co-operating fully with the inquiry, which could demand to see relevant emails and WhatsApp messages. No serving prime minister has ever been interviewed under caution in relation to an alleged breach of the law. Miss Symonds, who reportedly commissioned Miss Lytle to get rid of the ‘John Lewis nightmare’ decor left by former prime minister Theresa May, could also face questions.

The inquiries follow a string of revelations in the Mail of how Tory donor Lord Brownlow paid £58,000 in an apparent attempt to gloss over the fact that the redecoration bill was met by Conservative HQ in the first instance. Mr Johnson has consistently denied any wrongdoing.

Last night Downing Street declined to comment.