London (CNN) Staff working for the British royal family have been summoned to a meeting in London, according to a royal source.

The meeting will take place at 10 a.m. (5 a.m. ET). CNN understands that the subject of the meeting is "significant" but that there was no cause for alarm.

It is normal for royal staff to be first informed of any significant news regarding the royal family, before a public announcement.

The meeting of senior staff was called by the Lord Chamberlain, the most senior member of Queen Elizabeth II's household staff.

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