It cannot be an easy job following in the footsteps of one of the world’s most idolised royals, but the Duchess of Cornwall today staked her claim over Diana, the Princess of Wales, in at least one crucial area – the diplomacy of fashion.

At a visit to the Badshahi Mosque in Lahore, the Duchess made sure she was fully covered, wearing a traditional dove-grey tunic which fell well below the knees with ivory palazzo trousers, unlike her predecessor who caused something of an outcry upon a visit to the same mosque in 1991.

Hardline mullahs were outraged when the Princess of Wales turned up to tour the religious site, built by the Mogul emperor Aurangzeb, with her knees on show in a skirt they considered far too short for the sacred precincts.

Such was the chorus of disapproval that a criminal prosecution was filed against the mosque’s imam, Mufti Molana Abdul Qadir Azad, but fortunately, the case was eventually dismissed and enraged mullahs ordered to stop wasting the judge’s time.

But although the Duchess decided wisely not to imitate the Princess’s wardrobe and kept her knees well covered, there was a brief but no doubt embarrassing moment of panic, when one of her ankles was fleetingly exposed for all to see.

The error occurred as she walked down the red-carpeted stairs after leaving the mosque and putting her shoes back on, with her trousers apparently getting caught up with a wayward pop sock.

Luckily, an aide was on standby for such emergencies and duly scurried over to alert the Duchess to the wardrobe malfunction, helping her untuck the material.

Despite the minor blip, the outfit – which the Duchess has worn on another Royal tour - appeared to go down a storm, enabling her to display frugality as well as modesty.

The dress, known as a shalwar kameez, made its previous appearance at a mosque in Cairo earlier this year, as part of a trip to Egypt, Saudi Arabia and India. During that tour too, the Duchess exhibited her practicality, by wearing items from her wardrobe more than once.

The visit to the mosque, which, with a capacity of 55,000 worshippers, is the second largest in Pakistan, came as the Prince of Wales and Duchess continue their five-day of the country.

It also incorporated a trip to a Sikh temple and an Anglican cathedral, in keeping with the theme of "interfaith harmony" that has dominated the rest of their high-security visit.

The whistle-stop religious excursion was carried out in less than three hours as part of a day trip to Lahore and took in the Sikh Gurdwara Dera Sahib and the 150-year old Anglican Cathedral Church of the Resurrection, where the pair were greeted by crowds of children waving Pakistani and British flags.

The royal couple were suitably obliging about adapting to each of the prayer sites’ dress codes in turn.

At the mosque, it was shoes off, with the Prince putting on soft black footcovers while the Duchess braved it barefoot, also wearing a dupatta shawl to cover her hair.

At the Sikh temple, the Prince too had to participate in the headwear trend, and was presented with a white topi hat while his wife was given a headscarf.

Finally, at the cathedral, the Duchess’ scarf was back around her neck.

On Monday the pair met President Pervez Musharraf in Islamabad, while on Tuesday they were forced to cancel a trip to the northwestern city of Peshawar due to protests against a military airstrike on a madrassa that killed 80 people.

Instead the Prince visited a women’s university in Rawalpindi before he and his wife saw ancient Buddhist ruins in the nearby town of Taxila town.

Yesterday, the couple met with survivors of the Kashmir earthquake in October 2005, which killed more than 80,000 and left 3 million others homeless.

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