JOHANNESBURG: The chief executive of Johannesburg Stock Exchange (JSE) will retire at the end of September after a transformative eight years at the helm of Africa's biggest securities exchange, the bourse said on Tuesday.

Nicky Newton-King has been instrumental in demutualising and listing JSE in 2006 as well as its acquisition of the South African Futures Exchange and the Bond Exchange of South Africa.

"She leaves the JSE stronger, more diverse, more technologically advanced, commercially savvy and client focused," Chairman Nonkululeko Nyembezi said.

Newton-King said: "There is a time at which a CEO needs to step back and allow an institution to be led by a new energy - and that time, for me, is now."

The board has appointed Commonwealth Bank of Australia executive Leila Fourie as group CEO with effect from October 1, the JSE said.

Fourie is no stranger to the exchange, having worked there for more than four years as an executive director of Post-Trade and Information.