Rapper says she's been working with Gaga "from afar" via email
Post Mermaid Ball bash will take place at London's Old Vic Tunnels
The Machinedrum produced track is taken from her 'Fantasea' mixtape
Producer claims Banks used his track without permission
The rapper starts her sold out UK tour later this week
The Prime Minister's wife is fond of the rudest song of last summer, according to Banks
The new promo comes ahead of the NY rapper's autumn UK tour dates
Grimes, Katy B and Metronomy also hit up the dance tent
But the '212' rapper says the hip-hop world is full of 'bird-brained men'
Rapper's first LP 'Broke With Expensive Taste' had originally been scheduled to come out in September