"The Queen sends her warmest good wishes to the people of Northern Ireland and looks forward to visiting in the future."
No further details were revealed about why the 95-year-old has been ordered to rest, sparking speculation among the public.
However, royal sources confirmed to multiple outlets that the Queen's decision to cancel the trip had nothing to do with COVID-19.
"We are told there is 'no cause for alarm' about the Queen's health," ITV's royal editor Chris Ship tweeted in the wake of the announcement.
Royal Central quoted an insider as saying the Queen is "feeling fine", and Town & Country's Victoria Murphy revealed on Twitter that it was "not COVID-19 related".
Northern Irish leaders sent their well-wishes to the Queen with Sir Jeffrey Donaldson, leader of the Democratic Unionist Party, tweeting that he trusts the Queen "will keep well and benefit from a period of rest".
This brief break is likely needed for the busy monarch, who has had a packed schedule of events and engagements in the weeks since she returned from her summer holiday in Scotland.
At 95, she's Britain's oldest monarch but that hasn't stopped her from continuing to carry out public royal duties well into her 90s.
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Even the death of her husband of 73 years, Prince Philip, didn't stop the Queen for long.
Her Majesty has thrown herself back into her work following his sad loss in April and has been busier than ever over these past few weeks.
It's understood that she will now retire to Windsor Castle for a few days' rest before returning to her planned royal duties next week.
In the meantime, other senior royals like Prince Charles, Princess Anne and Prince William may step up to attend some of the engagements she will be forced to miss.
These and other key royals have taken on more public responsibilities following Prince Philip's death in an effort to continue supporting the Queen.
Despite all this, Her Majesty revealed earlier this week that she doesn't view herself as being "old" even as she approaches her 96th birthday next year.
She declined the "Oldie of the Year" Award, stating through a private secretary that "you are as old as you feel, as such The Queen does not believe she meets the relevant criteria."
This story originally appeared on our sister site, Now To Love.