Ariana Grande knew she would marry Pete Davidson years before they started dating.

The 'No Tears Left To Cry' hitmaker appeared on 'The Tonight Show with Jimmy Fallon' to celebrate the release of her fourth album 'Sweetener' and she discussed the inspiration behind the track 'Pete Davidson', which Ariana is believed to have wrote just a week after they started dating.

Ariana, 25, talked about the beginnings of her romance with Pete, 24, and admits she knew he would go on to be his husband when they first met in March 2016 when she hosted an episode of 'Saturday Night Live' - the sketch show that the comedian stars on.

She said: ''Well, we met on 'SNL' like two, three years ago whenever that was, we've like never exchanged numbers or anything - we weren't even like friends for a long time.

''But I had the biggest crush in the world on him the whole time, like forever my friends used to make fun of me for all that stuff.

''But I like left his writer's room and we were like writing skits and stuff for the show and my tour manager was in the hallway. ''I'm not like a crushy person I don't have crushes on people I don't know, but I left and I like jokingly said to my tour manager, I was like, 'I'm marrying him 100 per cent.' I was like, I'm literally marrying him.' ''

The lyrics to the song 'Pete Davidson' includes lyrics such as: ''I thought you into my whole life / look at my mind yeah / no better place or time look how they align / universe must have my back, fell from the sky into my lap / and I know that you know you're my soul mate / I'm like ooh / my whole life I'm gonna be ready for you.''

Ariana's comments come in the same week that Pete revealed he knew he wanted to make the pop star his wife the first day he met her.

In an interview with GQ America magazine, he said: ''The day I met her, I was like, 'Hey, I'll marry you tomorrow.' She was calling my bluff.

''I sent her a picture [of engagement rings]. I was like, 'Do you like any of these?' She was like, 'Those are my favourite ones,' and I was like, 'Sick.' ''