The Queen, 86, has cancelled two more public appearances after being hospitalised for symptoms of gastroenteritis last week.
Buckingham Palace has announced she will not visit technology companies in London's Tech City on Wednesday or a chapel service for the Soldiers' and Airmen's Scriptures Association Service on Thursday.
The British monarch will continue to carry out her official duties within the palace, however.
A statement said: "The Queen continues to make a good recovery following her recent illness, and today she presented the Queen's Gold Medal for Poetry and held a series of audiences.
"However, regrettably, she will no longer attend the Tech City engagement planned for tomorrow, or the Soldiers' and Airmen's Scriptures Association Service at the Guards Chapel on Thursday.
"The Duke of York will represent The Queen at the Tech City visit, and The Duke of Edinburgh will attend the Guards Chapel Service as planned.
"Her Majesty will, however, continue with the usual rhythm of business at Buckingham Palace, including holding a Privy Council meeting tomorrow.
"The Queen hopes to resume her programme of official engagements next week."
Yesterday, a palace spokesperson gave an update on the Queen's health: "This time last week she was in hospital but she's in great spirits and apart from this is in good health and will be going to the reception in the evening.
"It's just the tail end of the symptoms, her condition has not worsened at all."
Earlier this week, the Queen did not attend a Commonwealth service at Westminster Abby. She later appeared at Marlborough House to sign the Commonwealth Charter.
Her visit to the King Edward VII Hospital in London was the first time she had spent the night in hospital for 10 years. Buckingham Palace said her visit was a precaution.
A spokesman said she remained in "good spirits" despite her illness.