On board a yacht surrounded by trusted friends with the clear blue ocean between her and prying eyes, it should have been a welcome break from reality for the embattled Princess of Wales.

But unearthed photos of Princess Diana on board a yacht in Italy with Kyril, Prince of Preslav, and the designer Valentino taken in 1990, two years before her separation from Prince Charles, show the late royal looking pensive and unsure.

The candid snap, posted to Instagram yesterday by Valentino co-founder Giancarlo Giammetti, shows the late royal with wet hair holding a drink, in a colourful print bikini with a purple shirt tied at her waist.