The Duchess of Cambridge – who is pregnant with her second child and has been suffering from acute morning sickness – had been due to undertake her first official solo overseas visit.
Prince William will instead take the place of his wife, Kensington Palace has said.
“The decision not to travel was taken by the duke and duchess on the advice of the duchess’s doctors,” it added.
The royal couple made their decision on Wednesday night.
Kensington Palace said Kate Middleton “continues to suffer from the effects of Hyperemesis Gravidarum”, a sickness condition that can require supplementary hydration, medication and nutrients.
The trip would have seen the duchess mark the 50th anniversary of Malta’s independence.
In her place, Prince William will visit the national library to see letters from past British monarchs Henry VIII and George II, take part in Independence Day celebrations and a complete a number of walkabouts.
“The duke is honored to represent Her Majesty the Queen on the visit, which commemorates the 50th anniversary of Malta’s independence.
“The visit itinerary remains unchanged,” the palace added in the statement.
Prince William and Kate Middleton had been forced to announce their second pregnancy earlier this month before the duchess passed the significant 12-week milestone.
The announcement was made because she had been suffering from acute sickness – as she had with her first child Prince George, who was born in July 2013.
Hyperemesis Gravidarum affects 3.5 per 1,000 pregnancies, causes severe vomiting and can lead to dehydration, weight loss and a build-up of toxins in the blood or urine, called ketosis.
Kate Middleton has been receiving treatment from doctors at Kensington Palace.
p5ses-EIopsImage source: Wikimedia Commons President-elect Donald Trump celebrated his election victory at the Ultimate Fighting…
Millions of voters across the US chose to return Donald Trump to the White House…
Donald Trump declares victory in the US election as he addresses jubilant supporters in Florida.…
Stocks around the world are rising as Donald Trump appears to be on the cusp…
Donald Trump has won Pennsylvania, North Carolina and Georgia and taken a lead over Kamala…
Quincy Jones, the celebrated musician and producer who worked with Michael Jackson, Frank Sinatra, Ray…