THE Queen and Prince Philip are both "fine" after she called an emergency meeting at Buckingham Palace this morning, sources say.
Speculation mounted after all senior staff and aides from royal residences across the country were mysteriously ordered to London.
Buckingham Palace is yet to give an official announcement, but said there is "no cause for concern".
Staff will be addressed by the Lord Chamberlain, the most senior officer of the Royal Household, and Private Secretary Sir Christopher Geidt shortly, according to the Daily Mail.
The meeting is not to do with either the Queen or Prince Philip's health, the BBC's Royal Correspondent said.
Social media has erupted in panic with many offering theories about the announcement, from abdication to far more serious issues.
The Mirror reports that even the most trusted of staff have been left in the cold as to what the meeting will be about.
"Although meetings involving the entire royal household are occasionally called, the way this has been done at the eleventh hour is highly unusual and suggests that there is something major to be disseminated," Mail Online reported.
News network OB satellite vans & reporters gathering outside Buckingham Palace right now pic.twitter.com/QqxpigZEKf— Zara (@strawdelish) May 4, 2017
Similar meetings are occasionally called by the Palace "but the way this has been done at the eleventh hour is highly unusual", a source told the Mail.
The news sparked speculation on social media that an announcement concerning the Queen, 91, or Prince Philip 95 could be imminent.
Sources say even Her Majesty's longest serving staff members do not know why the meeting has been called.
An official announcement is expected after the meeting has taken place at 10am.
A flag has been seen flying at full mast at the Palace this morning, indicating the Queen is in and everybody is well.
Prince Philip was pictured yesterday looking happy and healthy as he opened a new stand at Lord's cricket ground.
Meanwhile the Queen met Theresa May to mark the dissolution of Parliament for the General Election.
Parliament was officially dissolved at one minute past midnight- and voters will take to the polls on June 8.
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