In a series of tweets, the Welsh opera star said she was 'hurt' by the 'untrue rumours' and stated she'd only met the footballer on two occasions and also warned that her lawyers were involved.
"Dear Twitter friends," she wrote. "I've read some horrible rumours on here & want u 2 know I absolutely deny I've had an affair with David Beckham.
"The rumours are very hurtful, untrue & my lawyers tell me actionable."
The singer then went on to confirm she'd only met Becks twice and has never spent time with him alone.
"I've only met David twice: once at the Military Awards in 2010 & on a night out in the West End in Feb 2012. We were out in a group of friends & it was just a normal fun evening out," she wrote.
"Just so we are clear I have never been on my own with him and never arranged to meet up."
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