Prince Charles and the Duchess of Cornwall are preparing to go on their second overseas tour together, taking in Egypt, Saudi Arabia and India.
The Prince will speak in Cairo on promoting dialogue between faiths
The first stop on the two-week trip will be Cairo.
Clarence House said the tour will focus on promoting tolerance between faiths, sustainable agriculture and training and employment for young people.
The couple's first official foreign trip was to the United States in November.
In Cairo, the Prince will give a speech on the importance of dialogues between different faiths.
Egyptian security services have tightened security for the visit, which begins on 20 March, and the Prince's team of bodyguards will be on high alert.
Following several incidents in which foreigners were targeted, the UK Foreign Office warns of a high threat from terrorism in Egypt and Saudi Arabia, and urges vigilance in many parts of India.
Prince Charles and Diana, Princess of Wales, stopped off in Egypt on their 12-day honeymoon cruise aboard the royal yacht Britannia in August 1981.
In 1992, Diana paid a solo visit and was photographed outside the pyramids.