Australian singer Sia has hit back at online reports suggesting she is dating Twilight actor Robert Pattinson. The pair was rumoured to be romantically linked after they were spotted attending a Jay-Z and Justin Timberlake concert in Pasadena, California last Sunday (28Jul13) before heading out for drinks together later that week (beg29Jul13). However, the bisexual singer/songwriter took to her Twitter.com account on Saturday (03Aug13) to deny the rumours, writing, "As much as I love d**k, I'm not dating (Robert Pattinson). Can I go back to being completely irrelevant now?" Pattinson has previously been mistakenly linked to Elvis Presley's granddaughter Riley Keough and pop star Katy Perry following his split from actress Kristen Stewart earlier this year (13).