Sam Smith is reportedly working on a comeback song with Clean Bandit.

Sam Smith

Sam Smith

The 'Stay With Me' hitmaker is believed to have had his first studio session with the electronic pop trio - Grace Chatto, Jack Patterson and Luke Patterson - though Jack is keeping tight-lipped about the collaboration.

When quizzed about it, he said: "That's interesting, where did you hear that?"

Sam - who has been on hiatus since October 2015 following the tour in support of his debut album 'In The Lonely Hour' - has always admired what the 'Symphony' hitmakers do and has waited this long to work with them as the group's former violinist, Neil Milan - who parted ways with his bandmates in October last year - mocked his James Bond 'Spectre' theme 'Writing's On The Wall'.

A source told the Daily Star newspaper: "That [Neil's departure] opened the door again."

At the time, Neil said that the song was "just a flaccid copy of Michael Jackson's 'Thriller.'"

Clean Bandit would join producer Timbaland and Frances in working with Sam on his comeback.

Speaking her song with her pal, Frances, 23, recently said: "It was amazing. We wrote a song a few weeks ago for his second album so it was really fun."

The 'Latch' hitmaker is keeping his new material under wraps for now, as Frances revealed she is yet to hear any of his other new tracks.

She said: "He didn't have any on his phone. I'm sure I'll hear it at some point."

And Timbaland - who has collaborated with the likes of Sir Elton John, Fall Out Boy, Nelly Furtado and Missy Elliott - shared a selfie with Sam on Instagram recently, and captioned the post: "It was a pleasure working with this man @samsmithworld #puretalent #goodvibes #makingmemories and #timeless #music (sic)"

Sam has been working on new music from the very offset of his hiatus, according to Frances.

She said: "Sam is so lovely and so supportive so great. I think he is doing a bit of writing, but he is having the most deserved break. I just think he worked so hard and he is so amazing and he did so well. I think he has been seeing his family and having a bit of Sam time, which he really deserves."