Prince Charles' former closest aide Michael Fawcett allegedly co-ordinated with "fixers" over honours for a donor to The Prince's Foundation, an investigation into the cash for honours claims has found.
According to senior British journalist Rebecca English, Fawcett was also involved in directing money from a Saudi billionaire's foundation.
A spokesman for Clarence House said: "It is important to His Royal Highness that the charities which bear his name operate to the highest standards, in accordance with rules established by charity regulators."
He added, "We are taking this opportunity to reinforce guidance to these charities."
Michael Fawcett, Prince Charles' longest-serving and closest aide, has quit his role as head of The Prince's Foundation amid an alleged cash-for-honors scandal.
The Prince of Wales has denied any knowledge of the alleged offer of honors in return for donations.
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