He's made his name with his songs of heartbreak and unrequited love, but it seems Sam Smith is a smitten love kitten right now.

The huge-selling pop star has taken to Instagram to post some fun snaps of himself and his new fella - and to share an emotional message with fans.

[related]He wrote: "I know this is so so late but I left my phone on a wet surface and it wasn't working for New Years haha but HAPPY NEW YEAR!!

"2014 was the best year of my life so far. I started my year so lonely and still fully in love with someone who didn't love me back. Right now I feel so unbelievably loved back.

"You have all changed my life & I will forever be thankful. May we have many more New Years together. Can't wait to see you all in 2015 and sing my ass off for you.

"I'll never be able to fully thank you all but I will always write a huge paragraph now and then to attempt to.

"Be safe and sensible but also TURN UP. Love you all x Sam x #littlesailors"

And the 22-year-old warbler has shared a series of snaps of himself and his new BF Jonathan Zeizel larking about with pals in the Sydney sunshine.

He even mimicked the famous prow scene from Titanic with Zeizel in one pic, captioning it: "I'm flying Jack, I'm flying."