Venus and Serena Williams will tour Ghana, South Africa and Senegal. The tour will start later this year in South Africa, but tennis fans are more likely to see them on school playing fields than in competition.

Their mother, Oracene, arrives in South Africa on Tuesday as a prelude to their trip but has made it clear that the main purpose of their visit is promotional.

"Since there are no WTA tournament opportunities in Africa, the girls would like to travel to the continent to provide a few clinics for the youth - and possibly an exhibition," said Williams from Wimbledon.

"It has been a lifelong dream of mine to visit Africa and it is also important for Venus and Serena to experience their cultural and ethnic history.

"We want to tour some of the countries and perhaps become involved with programmes that impact on youth, women, health and education. They want to make a lasting contribution to their homeland."

Accompanying Williams on her trip to Africa will be Cora Masters Barry, wife of the former mayor of Washington DC, Marion Barry, founder of the Southeast Tennis and Learning Centre.

Oracene Williams is founder and CEO of the Owl Foundation based in Palm Springs, Florida, while Venus and Serena serve on the board.

The foundation is dedicated to maximising educational programmes for youth who have been evaluated as slow learners and who require special attention.

While on her tour to South Africa, Ghana and Senegal, Williams will meet with heads of state, ministers of sport, health and education as well as directors of organisations which sponsor programmes that impact on women, children and youth.

She will also scout possible sites to hold tennis clinics and exhibitions for Venus and Serena.

Williams will be in South Africa until July 15, before moving on to Ghana where she will stay until July 20. She will end her African tour in Senegal where she will be from July 20 to 27.