Prince William will visit New Zealand and Australia next week to tour areas devastated by recent natural disasters, St James's Palace has said.
The prince will travel to Christchurch, New Zealand, where more than 160 people died in an earthquake last month.
He will also go to Greymouth, near the site of the Pike River mine disaster in New Zealand in which 29 people died.
William will then travel to Australia, where he will visit areas hit by flooding in Queensland and Victoria.
The prince will visit the two countries on behalf of the Queen following invitations from the prime ministers of New Zealand and Australia
He will not be accompanied by his fiancee Kate Middleton on the trip which takes place from 17-21 March.
The prince will meet those affected by the recent disasters, and members of the emergency and other support services.
William will attend a national memorial service in Christchurch as well as carrying out other engagements in the area.
In Australia, he will go to several locations in Queensland over two days followed by a visit to north-west Victoria.
A St James's Palace spokesman said: "The prince's visit comes after an invitation from the prime ministers of New Zealand and Australia.
"William will be travelling on behalf of the Queen and the wider Royal Family."
The spokesman added: "The Royal Family have been watching the natural disasters with the same shock and sadness as everyone else.
"They wanted to show their solidarity with the people of New Zealand and Australia, and the decision was taken with the prime ministers' offices and the royal household that Prince William should attend and visit the countries."
The magnitude 6.3 earthquake struck the city of Christchurch on New Zealand's South Island on 22 February this year.
Also on the South Island, 29 miners became trapped by a gas explosion at the Pike River coal mine in Atarau on 19 November last year.
Parts of Australia were affected torrential rains starting in November last year, forcing rivers to burst their banks.
Prince William was last in New Zealand in January 2010, when he represented the Queen in Auckland and Wellington.
He made a private visit to Sydney and Melbourne in Australia the same month. He first visited Australia as a baby on his parents' tour in 1983.