The chief executive and chief financial officer of South Africa’s state ports monopoly Transnet have both quit the company, it has been confirmed.

Portia Derby will leave as chief exective at the end of October 2023, while Nonkululeko Dlamini, Transnet’s CFO has quit to join Telkom, South Africa’s listed phone company.

Transnet’s board has appointed Michelle Phillips, chief executive of Transnet Pipelines, as acting group chief executive with effect from 1 November 2023.

Transnet operates Africa’s busiest port in Durban, and other terminals and railways that move coal, iron ore and other natural resources to global markets.

But Transnet and its chief executive have come in for heavy criticism from miners and trade unions over the collapse in volumes handled by the company.

This month, Transnet reported losses of SAR 5.7bn ($302m) in the year to the end of March as a result of the collapse in freight volumes, reported The Financial Times.

At just over 50m tonnes, South Africa’s coal exports last year were its lowest since 1993, with the decrease attributed to cable theft and missing trains on a critical Transnet line.

Over the past two weeks, Glencore and Seriti Resources have started talks to cut hundreds of jobs in South Africa as their ability to export coal is stymied by inefficiencies at the freight company, reported Bloomberg.

Transnet’s rail operations were also affected by a strike last year, along with floods and power supply disruptions caused by the state-owned utility’s inability to meet demand, it said in its latest results.

Derby, who was appointed in 2020 by the government of South African President Cyril Ramaphosa, was described by Transnet as “steering the company through an extremely challenging period”.

In the summer, Philippines terminal operator International Container Terminal Services Inc (ICTSI) was selected to run South Africa’s largest port.

It was named as the preferred bidder for the 25-year joint venture, with Transnet Port Terminals (TPT) to operate and further develop the Durban Container Terminal (DCT) Pier 2.

Transnet said the partnership with ICTSI would “help reposition the terminal for best practice performance, ensuring growth in volume throughput, and will support the terminal in providing operational and commercial support to access global shipping line call routes”.

Derby said private sector participation in Pier 2 was a “key catalyst” for repositioning the Port of Durban as a container hub port.