They first snogged at Wills and Kate’s wedding in 2011 when they hooked up in a bathroom, say shock reports in the US.
And they are said to have rekindled the romance with a behind-closed-doors affair for the last three months.
The pair have apparently only ever been caught in the act by their older siblings.
OK! USA magazine also claims to have intimate details of how they spent their first “date”, and reckons they have fancied each other for years.
Party prince Harry, 31, allegedly first “noticed” Pippa, 32, as the rest of the world watched Kate and William get hitched.
Smooch The publication says the prince felt attracted to Kate’s Maid of Honour – who all but stole the show at the wedding due to her now famous backside.
Pippa and Harry are said to have spent the entire reception flirting.
An insider told the magazine: “At one point, Kate went to check her makeup and found them snogging in a bathroom.”
Kate, 33, was said to be unhappy about walking in on the smooch.
The article claims Harry vied for Pippa’s affection for months, but she did not want to upset the Duchess of Cambridge.
Both went on to date other people with Harry seeing Cressida Bonas, 26, and Chelsy Davy, 30, on and off for years.But OK! insists that Pippa and Harry never stopped fancying each other.
“There’s always been sexual tension between them,” the magazine’s source said.
In the last days of her three-year relationship with financier Nico Jackson, Pippa reportedly went to Harry’s home in tight jeans and sheer top.
The insider said “they sipped wine and then ate a pasta carbonara that he’d prepared himself”.
OK! does not say whether the two then got frisky.Clarence House declined to comment last night.
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