Anglo-Australian miner Rio Tinto says Simon Thompson will step down as chairman bowing to investor pressure over the destruction of two ancient Aboriginal rock shelters for an iron ore mine last year.

Thompson will resign following next year’s annual general meetings, while non-executive director Michael L’Estrange will also retire from the board after this year’s meetings, Rio said in a statement.

Analysts said last month Thompson would likely face increasing pressure over the board’s handling of the destruction of the Juukan Gorge rock shelters in Western Australia’s Pilbara region after an Indigenous group accused him of breaking a personal promise.

The destruction of the 46,000-year-old shelters sparked public and investor uproar that led to the resignation of CEO Jean-Sebastien Jacques and two deputies.

“I am ultimately accountable for the failings that led to this tragic event,” Thompson said on Wednesday.

In a statement the National Native Title Council said it “welcomed” the news, and CEO Jamie Lowe said significant law reform in Western Australia was now “paramount.”

L’Estrange produced a highly criticised internal report into the Juukan Gorge fiasco.

The miner last month outlined a revamped cultural heritage management process, acknowledging its destruction of the sacred site had badly damaged its standing among stakeholders and its employees.

Rio blew up the 46,000-year-old caves to extract $188 million worth of high-grade iron ore.

The incident devastated traditional owners, the Puutu Kunti Kurrama and Pinikura people, and prompted enormous global backlash.

Rio nonetheless posted its best annual earnings since 2011 and declared a record dividend on the back of strong commodity prices.

Thompson has previously said the board noted those involved in the debacle “did not deliberately cause the events to happen, they did not do anything unlawful, nor did they engage in fraudulent or dishonest behaviour or wilfully neglect their duties”.

The Australian Council of Superannuation Investors welcomed Wednesday’s announcement.

“The destruction of the Juukan caves resulted in a devastating cultural loss. Today’s announcement is a step towards the company rebuilding relationships with traditional owners,” CEO Louise Davidson said.

“In particular, investors would like to see the board increase its connection with Australian operations and communities, as well as an increase in mining experience.”

Australian Associated Press