While officials were initially mum on the reason for the meeting, they have announced that Prince Philip will retire from public life later this summer.
The Duke of Edinburgh will attend previously scheduled events between now and August, according to Buckingham Palace.
While he is expected to retain membership as president or member of over 780 organizations, the palace said he will no longer play an active role.
The emergency meeting was first reported by the Daily Mail. The Royal Standard, a flag which signifies when Queen Elizabeth II is inside the palace, was up, according to ABC News.
The palace did not release a statement or comment about the meeting initially.
The news set off a frenzy on social media with people speculating on what the emergency meeting could be about, ranging from the death of Prince Philip to Prince Harry's relationship.