The 'She Looks So Perfect' hitmakers are currently touring with the British band for the second time, and though they get on well, they won't be recording a duet with their pals.
Asked if they would team up with One Direction, Calum Hood said: ''We are two completely different bands.''
Luke Hemmings added: ''We might write with them at some point. If we were going to do a song it'd be with someone that's cool and up-and-coming.''
The group's career has escalated since they first toured with the 'Little Things' singers last year and they admit being on the road this time around has been a different experience.
Ashton Irwin said on 'Live from MTV': ''I think it's been different in a few ways, we got to go to Europe for the first time and without them [One Direction], we would have never gotten to meet some of the fans, so that was incredible.
''There's a few more people singing along to our songs, which is nice. That's just a beautiful thing.''
Another thing that has changed this tour is there is less ''nudity'', after 1D star Harry Styles pranked the support act by invading their dressing room to throw fruit at them while nude last year.
Ashton said: ''No, naked Harry Styles, which is a bit disappointing. It's a decrease of nudity on the tour this year.''