Queen Elizabeth has been hospitalized over an apparent stomach infection that has ailed her for days, Buckingham Palace said Sunday. The monarch will have to cancel a visit to Rome and other engagements as she recovers.

The palace said the 86-year-old British monarch had experienced symptoms of gastroenteritis and was being examined at London's King Edward VII Hospital.

"As a precaution, all official engagements for this week will regrettably be either postponed or cancelled," the palace said in a statement.

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A press officer at Buckingham Palace said the Queen is "only expected to spend two days in hospital."

"The Queen was admitted to King Edward VII hospital at around 3 p.m. today… She is otherwise in good health. Her hospitalization is precautionary. All official engagements will regrettably be postponed or cancelled for one week."

He mentioned she had carried out a medal presentation at Windsor Castle before being driven to the hospital. He said "we will see how it goes but the Queen is only expected to spend 2 days in hospital."

Elizabeth's two-day trip to Rome had been planned to start Wednesday. A palace spokeswoman said the trip may be "reinstated" at a later date.

The office of the Governor General of Canada issued a statement Sunday conveying best wishes and hope for a speedy recovery.

"My wife, Sharon, and I were distressed to receive word that Her Majesty Queen Elizabeth II has been hospitalized," said Governor General David Johnston.

"On behalf of all Canadians, we offer our best wishes to the Queen for a quick and full recovery."

Prime Minister Stephen Harper sent out his wishes to the Queen via his Twitter account.

"Laureen and I are sending our best wishes to Her Majesty for a speedy recovery," said Harper's tweet.

The symptoms of gastroenteritis — vomiting and diarrhea — usually pass after one or two days, although they can be more severe in older or otherwise vulnerable people. Dehydration is a common complication.

The illness was first announced Friday, and the Queen had to cancel a visit Swansea, Wales, on Saturday to present leeks — a national symbol — to soldiers of the Royal Welsh Regiment in honour of Wales' national day, St. David's Day. She instead spent the day trying to recover at Windsor Castle, but appears to have had trouble kicking the bug.

A doctor not involved in the Queen's treatment said that if medical officials determined she had lost too much fluid, she could be rehydrated intravenously.

"I suspect that she's being assessed and that it'll be a relatively uncomplicated treatment," Dr. Chaand Nagpaul told Sky News television. "It is very much about ensuring that the body receives the fluid it needs."

Elizabeth is one of Britain's longest-reigning monarchs and has rarely let ill health get in the way of her still-busy schedule.

About five months ago, she cancelled an engagement due to a bad back. The last time Elizabeth was hospitalized was in 2003, when she had arthroscopic surgery to remove torn cartilage from her knee.

The Queen has undertaken a number of engagements over the past week. On Tuesday, she met the new archbishop of Canterbury, Justin Welby, at Buckingham Palace, and on Thursday she presented a host of Olympic stars, including track and field star Jessica Ennis, with honours during an investiture ceremony.

Ingrid Seward, the editor of the Britain's Majesty Magazine, said that the queen "probably agreed to be hospitalized in order to get better quickly."

"Everybody will want to be wishing her a speedy recovery," she told Sky.