The Maltese government has congratulated the Duke and Duchess of Cambridge following this morning’s announcement that Kate Middleton is expecting her second baby.
A government spokesman said the British government had been in contact with the Maltese government over the visit to Malta which the Duchess is due to make on September 20-21.
He echoed a statement by Kensington Palace that a decision on the trip would be taken closer to the date.
The Duchess is suffering from acute morning sickness, as she did with her first pregnancy, and is being treated by doctors at Kensington Palace. She dropped out from a planned engagement in Oxford today with Prince William.
The Malta trip would be her first solo royal engagement abroad.
British Prime Minister David Cameron offered his congratulations to the couple today, saying: "Many congratulations to the Duke and Duchess of Cambridge. I'm delighted by the happy news that they're expecting another baby."
As with her first pregnancy, the Duchess is suffering from hyperemesis gravidarum - acute morning sickness.
She is being treated by doctors at Kensington Palace and royal officials said she will no longer be attending a planned engagement in Oxford today.
The full statement announcing the pregnancy said: "Their Royal Highnesses the Duke and Duchess of Cambridge are very pleased to announce that the Duchess of Cambridge is expecting their second child.
"The Queen and members of both families are delighted with the news.
"As with her first pregnancy, the Duchess is suffering from Hyperemesis Gravidarum.
"Her Royal Highness will no longer accompany the Duke of Cambridge on their planned engagement in Oxford today. The Duchess of Cambridge is being treated by doctors at Kensington Palace."
It comes around six weeks after Prince George celebrated his first birthday.
The couple's second child will become fourth in line to the throne, shifting Prince Harry further down the line of succession.
Kate's first pregnancy was revealed when she was just a few weeks pregnant after she was admitted to hospital suffering from severe morning sickness in December 2012.
Hyperemesis gravidarum, which 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.
It is understood that Kate's pregnancy has not passed the 12-week stage - a similar position to when she was struck by the illness when in the early stages of her first pregnancy.
A Kensington Palace spokesman said the Duchess's attendance at future events would be decided on a "case by case" basis.
A spokesman said: "We will be planning this on a case by case basis - it's too early to talk about Malta."
Rumours about a second child have been rife since earlier this year.
William fuelled the speculation in April when he told a woman who presented him with a lace shawl: "You might have to make another one soon."
The rumours were quashed later when Kate drank wine at a vineyard and took a white-knuckle jet boat ride.
Then in July one bookmaker suspended betting on an announcement
Today's news sparked betting on aspects from baby names to the child's hair colour in what bookmakers described as "the biggest novelty market of the year".
It generated excitement around the globe, with the hashtag "royalbaby" trending worldwide and in the UK.