Days after miner BHP launched its takeover bid for rival Anglo American in April, the CEOs of both headed for South Africa, where a condition to divest Anglo’s local platinum and iron ore assets was causing a political storm.

More than 20% of Anglo shares are held by South African investors, and the London-listed group’s presence is deemed of national value in the country, where it was founded in 1917 and employs more than 40 000 people.