The very public display of affection, in front of dozens of fellow skiers, came only a few hours after even more intimate revelries at a restaurant in the town.
It was not a wild night by Harry’s standards; no one was naked or wearing Nazi fancy dress.
Bear hug: Locked in a tight embrace on the slopes of the Verbier ski resort yesterday, Prince Harry and his society girlfriend Cressida Bonas seem to be closer than ever
Close: The very public display of affection, in front of dozens of fellow skiers, came only a few hours after even more intimate revelries at a restaurant in the town
The pair were said to have ‘kissed like love-struck teenagers in the back of a cinema’.
The other end of the same table was an altogether more sober affair. Harry’s uncle, Prince Andrew, whose 53rd birthday on Tuesday they were celebrating, sat with his ex-wife, Sarah, Duchess of York, and their two daughters, Princesses Beatrice and Eugenie.
Eugenie’s boyfriend, Jack Brooksbank, briefly strolled over chatted to Harry and Cressida. But for the most part they had eyes only for each other. The Yorks traditionally enjoy a week’s skiing in the resort every year to mark Prince Andrew’s birthday, often inviting photographers to capture the event. This time, perhaps not unsurprisingly, the invitation was not extended.
The family had booked a table for 20 at The Pot Luck, where they ordered steak and king prawns and drank £17 champagne cocktails.
In the spotlight: This week's events in Verbier could suggest that things are beginning to get serious between Prince Harry and Cressida Bonas. The model is spotted out in London previously
Shortly before midnight, Miss Bonas, who wore a minuscule black dress and heels, showing off a pair of endless legs, stood up and walked over to sit on Harry’s lap.
The pair then began to kiss, with Harry stroking the back of her head as they did so, in a passionate clinch for several minutes.
A witness said: ‘We couldn’t believe what we were seeing. They were not being discreet about it.
‘The Duchess of York and Eugenie sat just a few seats away at the time and seemed to be deliberately looking the other way, making polite conversation while it was happening.
‘Afterwards, Harry’s girl stayed sitting on his knee while they chatted to his friends.’
The diner went on to reveal: ‘At one point, a waiter brought over a tray of vodka and Red Bull and Harry shouted: “Free drinks on the house!” Everyone seemed to be having a great time.’
Although Prince Andrew left shortly afterwards, the younger royals went on to an exclusive bar above the restaurant, before moving to a basement nightclub, where they stayed until 3.30am.
Despite the late night, however, Harry and Cressida still hit the slopes yesterday morning and were again seen openly hugging and kissing on the slopes, which were packed with half-term visitors.
Both appeared to be extremely competent skiers and spent most of the day on the mountain.
Pole to pole: Harry shows touching concern for his girlfriend on their romantic break
The student, who wore a white woolly hat with a fur bobble and pink salopettes, appeared relaxed and could be seen laughing with the Duchess of York as they left the slopes.
She and Eugenie were also seen lying on the snow and giggling as they played with a large St Bernard dog.
Last summer’s disastrous Las Vegas stag trip, during which Harry, now 28, was pictured naked — a faux pas which reportedly led to him being dumped briefly by a furious Cressida — seems a very long time ago now.
So, for that matter, does his previous, long-term relationship with the Zimbabwean heiress Chelsy Davy, who dumped him in 2011, reportedly because she could not face the prospect of being in the spotlight as a royal wife.
Since Vegas, Harry, in his guise of Captain Wales of the Army Air Corps, has served a four-month tour of Afghanistan as a co-pilot in an Apache attack helicopter.
At the end of his service he talked of having a new maturity. A few months earlier, he had complained on American television that he would like to settle down, but girls were put off by his royal status.
So, do this week’s events in Verbier suggest matters are getting serious between him and the Stowe-educated Miss Bonas?
The couple are said to have started dating last May, though they only appeared as an item on the public radar when pictured leaving a Mayfair nightclub in July.
Cosy chat: The Duchess of York, so long excluded from royal circles, has a heart-to-heart with Cressida
Harry’s cousin and Miss Bonas’s good friend Princess Eugenie is said to have brought them together.
The daughter of renowned Old Harrovian businessman Jeffrey Bonas and Sixties model Lady Mary Curzon — who posed semi-naked for a coffee table photographic book and went on to get married and divorced four times — Cressida is a familiar figure in London’s upper-class social scene.
As a teenager, she was labelled by society bible Tatler as ‘really pretty, really nice and absolutely obsessed with Eva Cassidy (the late American singer)’.
After splitting up with Miss Davy, Harry was linked to a string of women, including model Florence Brudenell-Bruce. But Cressida seems to be the one he has been most smitten with.
Split: Prince Harry was previously in a long-term relationship with Chelsy Davy. The pair are pictured together in 2010
Last year she and Harry flew together to the Caribbean island of Necker for the birthday of tycoon Sir Richard Branson’s son Sam, who is engaged to be married to Miss Bonas’s beautiful half- sister, the actress Isabella Anstuther-Gough-Calthorpe.
This week’s ski holiday, to which the Prince had flown on budget airline easyJet, is significant in royal terms for more than one reason.
It is the first time in many, many years that Harry has been seen in public with the snubbed Duke of York’s ex-wife.
Sarah was robustly frozen out by the Royal Family after being photographed having her toes sucked by her ‘financial adviser’ in the South of France, an incident which precipitated her divorce from Prince Andrew.
And despite enjoying a close relationship with Harry and his brother William while they were growing up, they had little to do with Sarah after she fell out with their mother Diana, Princess of Wales, shortly before her death.
Andrew, however, has always championed his ex-wife and, despite the fact that she was pointedly not invited to the Duke and Duchess of Cambridge’s wedding, will no doubt be feeling pleased that his nephew Harry is rekindling their relationship once again, thanks to Cressida.
So, a thaw in royal relations. Miss Bonas seems to be melting hearts.