It means she will not undertake any official visits during this time.
The monarch will be unable to attend the Festival of Remembrance on Saturday, November 13.
But the head of state has the “firm intention” of leading the nation in honouring the country’s war dead on Remembrance Sunday on November 14.
The development comes after the Queen underwent tests in hospital last week and cancelled a two-day trip to Northern Ireland.
In a statement on Friday Buckingham Palace said: "Following on from their recent advice that the Queen should rest for a few days, Her Majesty's doctors have advised that she should continue to rest for at least the next two weeks.
"The doctors have advised that Her Majesty can continue to undertake light, desk-based duties during this time, including some virtual audiences, but not to undertake any official visits.
"Her Majesty regrets that this means she will be unable to attend the Festival of Remembrance on Saturday, November 13.
"However, it remains The Queen's firm intention to be present for the National Service of Remembrance on Remembrance Sunday, on November 14."
Palace sources say she is in “good spirits” and it is understood she recorded her COP26 speech this afternoon - which will be played at the climate change summit she was forced to pull out of.
It was announced on Wednesday she would be unable to attend the meeting of world leaders in Glasgow next week.
The palace said she would deliver her address to delegates using a recorded video message instead.
She had resumed public engagements on Tuesday by meeting ambassadors via video link from Windsor Castle.
Sources say she is continuing with “light duties”.
Her Majesty’s Diary was said to be light for next week but her medical team and the Queen believe the move is “sensible” to help host organisations make plans.