The London-born star has joined forces with Miley, 26, for the new single 'Nothing Breaks Like A Heart' and for her new album, and Mark has hailed the talents of the American singer.
Mark - who has previously worked with the likes of Amy Winehouse and Bruno Mars - shared: ''We both knew there was chemistry there. That led me to work on Miley's record. She's really one of the greatest voices I've ever recorded.''
Mark - who split from his ex-wife, actress Josephine de La Baume, in 2017 - also opened up about the process of recording 'Nothing Breaks Like A Heart', saying the hit single ''started to write itself''.
Speaking to The Sun newspaper, he explained: ''I went through some s**t that meant the song started to write itself.
''It had been a while since I tried Miley, and I was like, 'f*** it'. She wrote right back.''
Mark also revealed the new single was much more straightforward to record than 'Uptown Funk', the chart-topping hit he recorded with Bruno Mars in 2014.
The British star - who is producing Miley's next album - recalled: ''The first day she came in, she recorded the chorus and wrote the verses. 'Uptown Funk' took seven months to write, so that's why I was so overjoyed to have something that felt so special.''
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