Miley Cyrus wants to collaborate with her sister Noah - but she won't answer her messages.

The 'Malibu' singer would love to do a duet with her younger sibling but has admitted they have barely any contact with one another, not even via cell phone.

When asked by a fan, ''Can you text Noah and tell her that the two of you need to record a song together?'', during an Ask Anything chat with iHeartRadio, Miley said: ''Ugh, if she'd ever text me back.''

The 24-year-old singer later added: ''Yeah, I text Noah all the time, and she never texts me back.''

Noah, 17, recently admitted she is ''proud'' to be Miley's sister and get the chance to hang out with her at big events, but she isn't thrilled by the comparisons between them.

She said: ''I'm so proud that Miley is my big sister, and to be able to go to these big radio shows and hang out with her. Of course no one wants to be compared to another person. But it's like, if a person can only see me for my sister, then that's really their problem.''

The 'Chasing Colors' singer - who released her debut single 'Make Me (Cry)' featuring Labrinth in 2016 - also revealed her famous dad Billy Ray Cyrus could have a song on her forthcoming record.

She said: ''Hopefully it will be done by this fall. I worked with so many amazing co-writers and producers on it. My dad might have a song on the album. I'm so blessed for this whole thing. I worked with some really talented, experienced writers.''