Madonna is teaming up with her ex-husband Sean Penn to raise cash for her Malawi charity.

The pop superstar has announced plans for an evening of "music, art, mischief and performance" at a Raising Malawi gig at Faena Forum in Miami Beach, Florida on 2 December (16), and the Oscar winner is on the bill.

Comedian Chris Rock, and Ariana Grande have also signed up to make appearances, while James Corden will host the event, which will be part of this year's (16) Art Basel festival.

All proceeds from the evening will benefit Raising Malawi, the non-profit organisation founded by Madonna in 2006. Madonna and her charity partners are currently working to build Malawi's first pediatric surgery and intensive care unit.

The new facility, to be named the Mercy James Institute of Pediatric Surgery and Intensive Care, is set to open in 2017 and will double the number of life-saving surgeries performed on children each year, provide intensive care after critical surgeries, and train specialised Malawian medical staff, according to a press release.

A spokesman says, "In a country with only four pediatric surgeons and where 50 per cent of the population is under the age of 15, this new facility will transform the lives of Malawian children."

Madonna stunned fans earlier this week (07Nov16), when she fronted a surprise New York gig on the eve of the U.S. presidential election. She performed a set at Washington Square Park hours before polls opened in the Big Apple.

The Hillary Clinton fan posted a photo of herself from the event on both Instagram and Twitter, playing a red guitar while wearing a Stars and Stripes hat with a black leather jacket, and captioned it: "You May say I'm a Dreamer... But I'm not the only one! Vote for H.R.C."

The pop superstar announced the last-minute show on Instagram and Twitter under a photo of herself flashing V-signs. She wrote: "Meet me in Washington Square Park at 7:30 Let's Go Hard For Hillary Clinton!"