The Charity Commission is to investigate the bitter dispute that led to the Duke of Sussex and several others resigning from the charity he co-founded.

The watchdog said it had opened a case to examine “concerns raised” about Sentebale, following claims made by its head Sophie Chandauka.

Ms Chandauka told the BBC she welcomed the move by the commission, which comes after she said she had “blown the whistle” on issues including bullying and harassment, and warned of the prince’s “toxicity” for the charity.

Prince Harry said: “What has transpired over the last week has been heartbreaking to witness, especially when such blatant lies hurt those who have invested decades in this shared goal.”

The duke, speaking on behalf of the former trustees and patrons, welcomed the watchdog’s announcement, saying it would be a “robust inquiry” which “we fully expect will unveil the truth that collectively forced us to resign”.

“We remain hopeful this will allow for the charity to be put in the right hands immediately, for the sake of the communities we serve,” said the prince.

The Charity Commission’s “regulatory compliance case” is the first step in assessing the complaints and allegations over what has happened at Sentebale, which was founded in 2006 to help children in southern Africa affected by HIV and Aids.

A statement from the watchdog said it was “in direct contact with parties who have raised concerns” and would gather evidence to see whether those running the charity, past and present, had complied with their “duties and responsibilities under charity law”.

An acrimonious boardroom battle led to Prince Harry, his co-founder Prince Seeiso of Lesotho and trustees resigning from their roles after Ms Chandauka had resisted attempts to remove her as chair.

“From the inception of Sentebale nearly 20 years ago, Prince Seeiso and I have had a clear goal – to support the children and young people in southern Africa in memory of our mothers,” said Prince Harry, responding to the charity watchdog’s announcement.

Ms Chandauka previously said she had reported the trustees to the Charity Commission, and made a whistleblower complaint about issues including what she described as an abuse of power, bullying, sexism and racism.

On Thursday, Ms Chandauka said in a statement that the concerns brought to the commission included “governance, administration and management matters”.

The Sentebale head said she hoped the public and donors would now see there was a new board of trustees “acting appropriately to demonstrate and ensure good governance and a healthy culture”.

Insiders have claimed personality clashes and tensions around leadership had added to Sentebale’s challenges – and the watchdog is likely to hear financial concerns from some of those formerly involved with running the charity.

“It is devastating that the relationship between the charity’s trustees and the chair of the board broke down beyond repair, creating an untenable situation,” those trustees leaving the charity said a statement.

Among the likely claims are that £500,000 of Sentebale’s money was spent on consultants in a strategy to get donations from wealthy individuals and foundations in the US, but which sources close to the former trustees say had not delivered adequate results.

The financial fears come despite the charity receiving an extra £1.2m from Prince Harry’s earnings from his best-selling memoir Spare.

A Sentebale spokeswoman rejected the claim that £500,000 had been spent on US consultants – and defended its approach to seeking new funds for the charity. Sources also claim Ms Chandauka had raised funding to cover the cost of the consultants and that her own family had become significant donors to the charity.

Sentebale told the BBC it had hired a US firm called Lebec to help build a new fundraising strategy, and that by October 2024 a team of six consultants had set up 65 key relationships with potential donors, who might help Sentebale in the future.

It said the 12-month deal with Lebec, a women-led strategy firm, had successfully delivered links to “high-net-worth individuals, family offices, corporations, foundations and partner non-profits”.

“Lebec provided the positioning strategy, the tools, and the insights to enter the US market successfully and with credibility,” a spokeswoman for Sentebale said.

The one-off donation from Prince Harry from his Spare book was “incredibly useful” but did not represent a long-term “funding pipeline”, said Sentebale.

The dispute has become increasingly personal.

Ms Chandauka argued the controversy around Prince Harry leaving the UK had become a barrier to potential donors.

She said the “toxicity” of Prince Harry’s brand was the “number one risk for this organisation”.

Ms Chandauka also spoke about a dispute over a video at a fundraising polo match, where it had been claimed Meghan was manoeuvring her out of the way during a prize-giving ceremony.

“Prince Harry asked me to issue some sort of a statement in support of the duchess and I said I wouldn’t,” said Ms Chandauka.

Sources close to Prince Harry and Meghan have rejected suggestions there was any conflict or anything negative about how the prize line-up was organised, saying it had been misrepresented.

They say the full video with sound shows Meghan politely helping the group get ready for the photo by asking: “Do you want to come over here?”.

Ms Chandauka says she and her leadership team are focusing on the day-to-day operations of the charity, and looking forward to working with their supporters as “we recalibrate for an ambitious future”.