The 30-year-old singer and John, 42, have collaborated on the track 'Inside Friend', and they're set to donate the proceeds to the relief fund, which supports music creators and professionals whose livelihoods are being affected by the coronavirus pandemic.
Speaking about the new record, Leon explained: ''The concept for 'Inside Friend' came about from Mayer and I joking around in the studio about what an ideal date for an introvert or homebody like myself would be.
''I tour most of the year, so I'd rather invite a gal over to lounge comfortably in the crib as opposed to go out somewhere crowded.''
Leon hopes the song will provide some relief for fans whilst they're in the midst of a lockdown due to the pandemic.
He shared: '''Inside Friend' stayed on the back burner for a while because it didn't fit within the context of my third project, but the current state we're in globally compelled us to dig this back up and finish it.
''I hope people find it soothing and uplifting while we hole up indoors and get through this.''
Leon - whose last album, 'Good Thing', was released back in 2018 - is also set to appear on John's new web series, 'Current Mood'. Fans of the acclaimed duo will be able to hear them discussing their new collaboration via John's Instagram account on Sunday (12.04.20).
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