Williams sisters due in Africa

Lagos - American tennis stars Serena and Venus Williams are set to arrive in Nigeria's largest city on Tuesday as part of a two-nation tour that will see them play exhibition matches to promote women's rights.

The sisters are both counted among the United States' most accomplished athletes, sharing 22 major women's singles championships between them.

Their trip is aimed at promoting "the role that women play in shifting perceptions and encouraging development at all levels across the African continent," said a statement from the Breaking The Mould initiative they are representing.

Serena, 31, and Venus, 32, are due to meet the governor of Lagos state, hold a tennis clinic at an exclusive club, visit a puberty education class for girls and play an exhibition match before heading to South Africa on November 2.

"They are coming to Lagos to encourage more women to break moulds that have stood between them and their potentials," the statement said.

Gender disparity is an acute problem in Nigeria, Africa's most populous country of roughly 160 million people, with the most glaring divides existing in the mainly Muslim north.

Worldwide, Nigeria ranks 118 out of 134 countries on the Gender Equality Index, a British Council study released in May said.