Sunshine Sachs worked alongside the team at Archewell Foundation, but HELLO! understands all communications from Meghan and Prince Harry are now being handled internally, although they remain close to the team.
WATCH: Harry and Meghan's touching moments during the the funeral
Although news of the separation has only recently emerged, HELLO! understands the two entities had always planned to separate following the formation of the Archewell Foundation and have maintained a good relationship, and even work together from time to time.
Sunshine Sachs worked with Meghan when she was an actress on the TV show Suits, and Meghan remained close to publicist Keleigh Thomas Morgan, who attended the royal's 2018 wedding. Keleigh was said to be working with the couple to build Sussex Royal, The Foundation of the Duke and Duchess of Sussex, before they stepped back as working royals.
At the time, the decision to hire the firm raised eyebrows in royal circles given that traditional PR would be handled by Palace staff. Sunshine Sachs specializes in 'crisis communications' for celebrities, with an impressive roster that has included the likes of Leonardo DiCaprio, Natalie Portman, Barbra Streisand and Jennifer Lopez.
The confirmation comes shortly after a particularly difficult time for the pair as Harry was left heartbroken following the death of his beloved grandmother.
Meghan worked with Keleigh while on Suits
The couple were scheduled to be in Europe for several charity events in early September but extended their stay by almost three weeks after the Queen's passing on 8 September and the funeral on 19 September.
Harry and Meghan reunited with his family and were seen on 10 September doing a walkabout around Windsor with the Prince and Princess of Wales.
Harry and Meghan joined William and Kate for a Windsor walkabout
News of the split also comes as the pair's multi-million dollar deals remain up in the air.
Harry, 37, is writing a memoir with the American ghostwriter, JR Moehringer, but it was reported that a spokesperson for Penguin Random House confirmed that it does not yet have a publication date – and would not confirm whether or not the book would still be released this year.
As part of their $100 million deal with the streaming service Netflix, Oscar-nominated director Liz Garbus is reportedly working on a docu-series about their lives, although it remains unclear when it may be released.
The pair were picture with film crews in New York City
The couple rounded off 2020 with the launch of their Archewell Audio podcast series in partnership with Spotify. A Holiday Special saw special guest appearances from Sir Elton John, James Corden and Harry and Meghan's son, Archie, who giggled adorably at the end of the episode.
However it took another 18 months for Meghan's podcast Archetypes to be released, and new episodes have now been put on hold for the duration of the mourning period for the Queen.
Three full episodes of the audio series have been released since its launch on August 23, featuring conversations with veteran tennis player Serena Williams, pop star Mariah Carey and actress and producer Mindy Kaling.
A message on the podcast's Spotify page now confirms: "New episodes of Archetypes will be paused during the official mourning period for Her Majesty The Queen Elizabeth II."
The period of 'royal mourning' has now finished after the Queen's funeral was held on Monday September 19.
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