Sir Cliff Richard has revealed he would like to share a duet with Rihanna or Lady Gaga - as long as the song is up to scratch.
The Devil Woman singer, 71, has collaborated with stars such as Sir Elton John in the past, but said he would be up for warbling with a modern pop diva.
Sir Cliff said: "Somebody asked me if I'd like to sing with Rihanna and I thought 'Who wouldn't?'
"She looks fantastic, she's got a great voice, but in the case of duets, if it's feasible, it's always a matter of what the song is.
"If we both like the song, that's the best way to do a duet. I couldn't just say, 'yes, I'll come', and then sing some dance thing I don't like."
He said he would be keen to team up with Lady Gaga if she was willing.
"Well, Lady Gaga's got a great voice. These people are great singers. It would be dependent on whether they wanted to sing with someone like me," Sir Cliff told the Press Association.
"I have nothing to offer them in America, yet, but in the rest of the world I'm known, so I guess it's feasible to do duets with people like that but it's not just my choice, it has to be their choice as well."
Sir Cliff - who released his Soulicious duets album and DVD earlier this year - added: "For me it's no problem at all. I've sung with other people, this is my second duets album and I must admit I do like tangling tonsils with other artists - when I listen to the record I think, 'that's me with Percy Sledge, that's me with Roberta Flack', so yeah I'm open to all of it really."