Bruno Mars has joked that his new collaboration track, 'Lighters', came about after beating Eminem in a rap battle.

The 'Grenade' singer, who shot to instant fame after releasing his hit single 'Just The Way You Are', has teamed up with rapper Royce Da 5'9" to star on a track for his Bad Meets Evil project. The addition of Eminem to the track comes after Mars challenged the '8 Mile' stars ability.

Bruno Mars commented on 'Lighters': "It was a freestyle battle. I said, 'Yo, Em, if I beat you, you're gonna have to do a song with me!' I shut him down right then and there."

Despite working with one of the biggest stars in hip-hop, Mars is still extremely focused on his solo work. He has said he is "extremely proud of" his new record.

Mars further commented, "I'm definitely thinking about what's next. I've got a song that I just wrote that I'm extremely proud of and I worked really hard on, and it's gonna come out soon. But this is just the very beginning and there's a lot more to come."

Be sure to check out the new video for 'Lighters' here: