The Queen will meet senior royals in Sandringham later to discuss the future roles of the Duke and Duchess of Sussex.
Prince Harry, the Duke of Cambridge and the Prince of Wales will all attend the meeting, while Meghan is expected join the discussion by phone from Canada.
The Sussexes say they plan to step back as senior members of the Royal Family.
BBC royal correspondent Jonny Dymond said a deal “might take time”.
Prince Charles has returned from Oman for the talks after attending a condolence ceremony following the death of Sultan Qaboos bin Said Al Said.
Prince Harry is understood to be travelling to Sandringham from Frogmore Cottage, his home in Windsor.
It is hoped the talks will produce a “next step” on the way to defining the couple’s new relationship with the Royal Family – in line with the Queen’s wish to find a solution within days.