Prince William and Harry solo travellers

May 11, 2010, 12:29 GMT

Britain's Princes William and Harry are set to go on their first joint overseas tour next month.

The young royals will visit southern African countries, including Botswana and Lesotho, before travelling to Cape Town in South Africa where they will watch the England soccer team play their World Cup match against Algeria.

However, the princes - who will be supporting England's bid to host the 2018 World Cup - will not be able to fly together on the tour because royal rules forbid them.

A palace source told The Times newspaper: "Particularly after the death of the Polish president, it is something we take very seriously."

The English Football Association - of which William is president - invited the princes to go to South Africa to support the 2018 bid, where they will attend a reception to meet members of the FIFA executive committee.

It was also seen as the ideal opportunity for William and Harry to oversee the work of the two charities they are heavily involved with.

William is patron of the Tusk Trust, which overseas conservation and humanitarian work in Botswana, while Harry is patron and co-founder with Prince Seeiso of Lesotho of Sentebale, which helps children and orphans in the mountain kingdom.