Demi Lovato's fiancé Jordan 'Jutes' Lutes "almost broke down crying" during his romantic musical proposal.

The 33-year-old singer-songwriter penned a proposal song to ask for the 32-year-old singer's hand in marriage and recalled how nerve-wracking it was getting it right on the big day, as he is not a seasoned guitar player.

Appearing on 'The Viall Files' podcast, he shared: "I wrote a song.

"I'm not a guitar player, but I can kind of play some chords. So it took me like, a week, just to write the chords for this song. And then I wrote a song, and then I practiced it.

He added: "Again, I'm not a guitar player, so rehearsing this song ends in 'Will you marry me?' was really difficult.

"I would mess up like three out of four times, so I was like when it comes time to do this like I just got to get lucky and just nail it."

Jutes continued: "I definitely almost broke down crying a few times."

The musician wanted to make sure Demi wasn't expecting anything so made sure she was kept busy.

He said: "I knew that she wasn't expecting it when I did it and that's why I did it then ... I wanted to catch her off guard.

"I mean, obviously, we had mentioned like you know wanting to be married and stuff like that."

The 'Cool for the Summer' singer started planning her nuptials just weeks after the proposal in December to minimise the stress of the big day.

During a recent appearance on 'The Tonight Show Starring Jimmy Fallon', Demi explained: "We have been planning the wedding for quite some time now. We got engaged in December and met with a wedding planner, like, a month later ... [I] wanted to be ahead of it".

When asked if she would be performing at the wedding, Demi replied: "I am not" before adding that they want the big day to be as stress-free as possible.

She added: "I want this to feel not anything like work".