The 'She's A Lady' hitmaker has grown close to the 'Naked Gun' actress since his beloved wife Linda died of cancer last year, but insisted they are not in a romantic relationship.
He told the Daily Star Sunday: ''Priscilla is a friend of mine. I've known her for years. But it's not true that we're dating or in a relationship. We are just friends. But good friends.'
Meanwhile, Tom, 76, recently admitted he's unsure how Priscilla's late husband Elvis Presley would feel about them spending time together.
The star said: ''I really don't know how Elvis would feel about us having dinner together - he probably wouldn't be too sure.
''But Elvis was a great man. It's nice to know that Priscilla and I are still in touch after all this time.''
Tom also revealed that the pair bonded over his song 'Elvis Presley Blues' from his 2005 album 'Long Lost Suitcase', but that they don't spend much time talking about music.
He said: ''I did a song on my last album called 'Elvis Presley Blues' and she liked it because she said it was a beautiful tribute to Elvis and she enjoyed it.
''Musically, that's about as much as we talk about. But she's been a friend of mine since 1968 when I first met her with Elvis.''
Explaining their relationship, he added: ''We were friends and Elvis passed away of course. But you know, we've kept in touch.
''We've been in each other's lives for years and she is one of a bunch of people that I know in Los Angeles and we do hang out.''
Tom and Priscilla, 71 - who previously dated 'Pop Idol' boss Nigel Lythgoe for three years and enjoyed a romance with singer Julio Iglesias - first met in 1968 while she was still married to Elvis Presley and remained friends even after the 'Blue Suede Shoes' hitmaker passed away in 1977.
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