Rumours about Kate Middleton's "flirt fest" with Sir Ben Ainslie have been debunked. Gossip Cop has said there is no truth to Star magazine's report that said the two got cosy right in front of Prince William during Portsmouth's leg of the America's Cup on 24 July.

The magazine's report that said the Duchess of Cambridge acted like a "giddy schoolgirl" when with the British Olympic sailor was "rubbish", a source at the America's Cup told the rumour debunking website.

Gossip Cop has said that the magazine's report that had said the prince's presence at the event "didn't stop Kate from flirting merrily with the sexy skipper" was "all fabricated".

"Kate is like a giddy schoolgirl around Ben... She totally adores him," an alleged source had told Star magazine as cited by Gossip Cop. "[Middleton] toyed with her hair and batted her eyelashes, while her husband stood by, looking a bit like a third wheel," the source said

"Kate was all aglow and couldn't wipe the smile off her face," the alleged source said.

The Duke and Duchess of Cambridge were spotted cheering Ainslie's Land Rover BAR team during the Portsmouth leg of the America's Cup World Series.

The magazine also reported that the "crush [between Middleton and Ainslie] has been building for a while now". The report further said that "sparks" between the two first kicked off at the 2012 summer Olympics in London, where Ainslie won a gold medal, and again in May when Prince William's wife went on a training ride on his new Catamaran.

"[Ainslie] really floats her boat," the source said.

Gossip Cop also said that the rumours of the two flirting with each other comes on the heels of a previous report that claimed Middleton and Ainslie were flirting with each other during a training session in May.

The rumour was debunked at that time after a royal insider told the website that the 34-year-old mother having a crush on the Olympic sailor was "nonsense". The website also said that it previously had debunked the magazine's cover story that claimed Middleton was pregnant with baby number three.

Prince William and Kate Middleton
Kate Middleton presents Sir Ben Ainslie with the America's Cup 2016 trophy on stage at the America's Cup World Series AFP/Getty