The pop superstar's 15-year-old son Rocco sparked an international legal fight between his New York-based mother and his father, British filmmaker Guy Ritchie, after refusing to return to the U.S. following a December (15) visit with his dad, his stepmother Jacqui Ainsley, and his half-siblings Rafael, Rivka and Levi.

Madonna subsequently filed legal papers in both the Big Apple and London, where she accused Ritchie of effectively kidnapping the teenager by allowing Rocco to stay against her wishes.

The case was heard in Manhattan Supreme Court last week (02Mar16), when Justice Deborah Kaplan scolded Madonna and her ex-husband, who both phoned in for the hearing, for dragging out the dispute in court instead of working together to find the best solution for their son.

She allowed Rocco to stay with Ritchie for the time being, and gave the warring pair until 1 June (16) to try and resolve the case amicably. Another hearing is set for later this month (Mar16).

Editors at the Mail on Sunday report Madonna is "bereft", and has conceded defeat to her ex-husband, admitting to close friends that she will let her son remain in the U.K.

The pop icon addressed the ongoing custody battle during the New Zealand leg of her Rebel Heart tour on Friday, and declared her undying love for her wayward teenage son.

Sitting on a chair in front of the 12,000-strong crowd, she said, "There is no love stronger than a mother for her son. And if I talk about him too much... I might cry."

Visibly distressed and holding back tears, she told the audience she would be singing her song La Vie En Rose for Rocco.

"I would like to dedicate this song to him - it's a love song for a man but I know he will need one, one day," she said. "I hope he hears this somewhere and he knows how much I miss him."