Queen Elizabeth II has summoned her grandson Prince Harry for a crisis meeting to discuss future arrangements for him and his wife, Meghan, following the couple's shock announcement that they want to step back from royal duties.

Harry's father, Prince Charles, heir to the throne, and his elder brother, Prince William, will also attend the meeting, due to take place on Monday at the queen's Sandringham estate in Norfolk, eastern England, a Buckingham Palace source said.

Meghan, an American former TV actress, will try to join via telephone from Canada, where she returned earlier last week to rejoin the couple's baby son, Archie.