Buckingham Palace has reportedly hired independent external investigators to manage the probe into claims that Meghan Markle bullied royal staff.
Royal officials have opted to use a third-party law firm to take of the investigation rather than conduct the inquiry internally, the Sunday Times reports.
The investigators are expected to to take to former and current staff who were unable to give evidence at a recent privacy court case involving the duchess.
The Times claims Meghan and Prince Harry are not expected to be invited to take part in the investigation even though they wrote to the palace about it.
The investigation was launched after two senior members of staff claimed that they were bullied by Meghan - allegations the Duchess of Sussex denies.
Another worker said they had been “humiliated” by the 39-year-old.
Meghan, who is expecting the couple's second child, has said she is "saddened" by the claims.
Meghan's spokesperson has said of the bullying claims: "The duchess is saddened by this latest attack on her character, particularly as someone who has been the target of bullying herself and is deeply committed to supporting those who have experienced pain and trauma."
In 2018 Jason Knauf, who was the Sussexes’ communications secretary at the time, made a bullying complaint in an apparent attempt to force Buckingham Palace to protect staff.
In an email to a senior courtier Mr Knauf, who now heads the Duke and Duchess of Cambridge’s charitable foundation, described Meghan's behaviour as “totally unacceptable” and claimed she “seems intent on always having someone in her sights.”
He also said: “I am very concerned that the duchess was able to bully two PAs out of the household in the past year.”
The email was forwarded to the palace's HR department but the complaint was not escalated until this year.
The investigation aims to “learn lessons” by taking evidence from members of staff past and present.
It is believed that the palace does not want it to “be played out in public” so that workers who are involved “feel comfortable”.
There is no set time frame for the inquiry but it is thought it will 'begin soon'.
A royal source told the Times: “It will take as long as it will takes.”
A palace spokesman told the paper they are “committed” to looking into the circumstances around the allegations from former staff of the Duke and Duchess of Sussex and will not be providing a “public commentary on it”.
The Mirror contacted Buckingham Palace for a comment.
The news comes a week after Meghan and Harry’s bombshell interview with Oprah Winfrey where they made shocking claims of revelations including a racism claim.
Meghan, whose mum is black, said she became suicidal while pregnant as a senior royal and said a family member had expressed concerns about Archie's skin tone.
Buckingham Palace released a statement 48 hours after the explosive claims saying while “some recollections may vary” they are taken “very seriously”.
They added the claims would but be addressed by the family privately.
Harry also claimed that his father Prince Charles stopped taking his calls after the Sussexes' shock break from the royal family.
The Prince of Wales was reportedly "deeply hurt" by the couple's interview but insiders say he hopes to fix the damaged relationship with his son.
He is reportedly planning to repair the bond by getting in touch with Harry in the next few weeks.
On Friday Prince William denied his his family were racist during a visit to a school in east London with his wife Kate Middleton saying “we are not racist” when asked about the allegations by a journalist.
It has since emerged that the two brother haves “been in contact” for the first time since the interview went to air with sources claiming they had exchanged texts..
