Prince Charles, the heir to the British throne, accepted a £1 million ($1.19 million, 1.21 million euro) donation to his charitable trust from the family of 9/11 mastermind Osama bin Laden, The Sunday Times reported.

Although there is no suggestion of any wrongdoing by the Saudi family members, the revelation increases scrutiny on the 73-year-old prince's charity organisations, which have been rocked by allegations of criminal wrongdoing.

Several of his advisers urged Charles not to take the donation from family patriarch Bakr bin Laden and his brother Shafiq -- half-brothers of terror leader Osama -- according to sources cited by the paper. 

Charles, 73, agreed to the donation to the Prince of Wales Charitable Fund (PWCF) when he met with Bakr, 76, at Clarence House in London in 2013, despite objections of advisers from the trust and his office, the paper reported.

Ian Cheshire, chairman of PWCF, said the donation was agreed by the five trustees at the time. 

British police in February launched an investigation into another of Charles's charitable foundations over claims of a cash-for-honours scandal involving a Saudi businessman.

The head of The Prince's Foundation resigned last year after an internal investigation into the allegations.

Michael Fawcett, chief executive of the foundation, had initially agreed to suspend his duties following newspaper revelations about his links to a Saudi national.

The man, tycoon Mahfouz Marei Mubarak bin Mahfouz, had donated large sums to restoration projects of particular interest to Charles. 

Fawcett, a former valet to the Prince of Wales who has been close to Queen Elizabeth II's heir for decades, is alleged to have coordinated efforts to grant a royal honour and even UK citizenship to Mahfouz.

Mahfouz reportedly denies any wrongdoing.

The Charities Commission, which registers and oversees charities in England and Wales, said in November it had opened a formal probe into donations received by Mahfouz's charitable trust which were intended for the prince's foundation.

The Prince's Foundation, set up in 1986, is not regulated by the Charities Commission but is registered with the Scottish Charity Regulator.

The Scottish body in September launched its own probe into reports that the foundation accepted cash from a Russian banker previously convicted of money laundering.