The Duke and Duchess of Sussex attended an exclusive JP Morgan event in one of their first engagements since stepping down as senior royals, a palace source has said.

It is unclear whether the couple, who have pledged to become more financially independent, were paid for their roles as speakers at a summit the banking giant hosted in Miami on Thursday.

An unnamed source told the New York Post’s Page Six, which first reported the story, the couple “headlined” JP Morgan’s Alternative Investment Summit. “It was all very hush-hush, with a lot of security,” the source said.

Meghan was introduced by CBS News host Gayle King before she opened the floor to her husband at 1 Hotel in South Beach, Page Six reported.

The Mirror has reported that the event could have earned the couple up to £400,000, according to “public relations experts”.

It is reported that Harry spoke on the topic of mental health, which he has spoken about publicly in the past. In 2017, the duke told in a TV documentary how he had sought counselling after the death of his mother, Diana, Princess of Wales.

As of yet, there is no sign of the event on the couple’s Sussex Royal Instagram account.

Last month the couple announced to their 11.2 million followers that they would be stepping down from royal duties and spending more time in North America. They will no longer use their HRH titles, represent the Queen or carry out royal duties and military appointments.

Under an agreement reached with senior members of the royal family, which comes into effect in spring, they will no longer receive money from the taxpayer-funded sovereign grant. That has made up about 5% of their income. The remaining 95% of their income currently comes from the Duchy of Cornwall.

It is believed the couple will continue to receive money from Prince Charles under the new arrangement. It is unclear whether this will come from the duchy, his personal wealth or both.

The JP Morgan’s Alternative Investment Summit is held annually in Miami and attended by billionaires including the Microsoft founder, Bill Gates, and multimillionaire baseball player Alex Rodriguez.