Prince Harry and Meghan, the Duke and Duchess of Sussex, will stop using their HRH (his or her royal highness) titles as they are "no longer working members of the Royal Family," Buckingham Palace has said in a statement.
It comes after Harry and Meghan released a statement earlier this month detailing their desire to scale down their royal engagements and become "financially independent".
The royals said they planned to split their time between the United Kingdom and North America.
Buckingham Palace confirmed on Saturday that the Sussexes would no longer receive public funds for royal duties and will be "required to step back from Royal duties, including official military appointments."
Harry and Meghan will also repay £2.4 million (€2.8 million) to the UK government's Sovereign Grant for refurbishing their residence in the United Kingdom - Frogmore Cottage - as it will remain their UK home.
"Harry, Meghan and Archie will always be much loved members of my family," the Queen said in a statement. She said she recognised the "challenges they have experienced as a result of intense scrutiny over the last two years and support their wish for a more independent life."
The Queen added that she was "particularly proud of how Meghan has so quickly become one of the family."
The couple, who wanted to transition to new roles within the royal family, will "no longer formally represent The Queen" but will work to "uphold the values of Her Majesty," the palace statement said.
In 1996, the Queen removed HRH titles from Princess Diana and Sarah, Duchess of York, by issuing a letters patent stating that a "former wife" of a royal with the exception of widows would not be entitled to hold the "royal highness" title.
The announcement that Harry and Meghan will instead no longer use the titles follows face-to-face talks between Prince Harry, the Queen, who is his grandmother, as well as his father Prince Charles and brother Prince William to discuss his future role within the royal family.
Meghan admitted in an ITV documentary last year that she was struggling with the media attention, particularly after the birth of the couple's son Archie.
In an October statement announcing legal action against select British tabloids, Harry said he had been "a silent witness to her private suffering for too long."