His One Direction bandmates are said to have poked fun at him after he flirted and kissed ITV reporter Caroline Whitmore at the weekend, reports The Sun.
Styles has been romantically linked with several people since breaking up with Xtra Factor presenter Caroline Flack.
A source said: "Harry was the only one of the boys to kiss her - and he did it twice.
"That started the rest of the boys teasing him in front of her saying things like, 'Ooh - a kiss for Caroline. It wouldn't be the first time'.
"Harry tried to brush it off but the lads kept teasing them... making funny noises and dropping hints they were an item."
Whitmore said after her interview with the boyband in Liverpool: "He was very sweet. He was the only one to kiss me, and twice! He did blush."
Styles was recently revealed to have had an affair with married DJ Lucy Horobin, 32.
He was recently rumoured to be seeking a reunion with former girlfriend Caroline Flack.
The interview will air on Granada Reports - ITV's regional news magazine show for North West England - at 6pm this evening.
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