The One Direction star was linked to the X Factor winner last month, but she reportedly denied claims the pair are dating.
"I do have a crush on Leona, she's hot!" he told BBC Radio 1. "I have met her. She's hot. I haven't eaten dinner with her though. I'd like to highlight the fact I'm single. I am single!"
Speaking of his new haircut, he added: "I was doing a photoshoot for a certain magazine, and they said, 'What can we do with your hair?', and I was like, shave it off.
"We went shorter, and shorter, and this is it. I have naturally quite curly hair, so I had to straighten it every morning with a hairdryer. My mum was worried about me, she thought I'd got some clippers and done it myself."
Payne recently admitted that he worries about how bandmate Zayn Malik is coping with fame.
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