MELBOURNE – Fortescue Metals Group said on Friday it will review plans at an iron ore mine in Western Australia after an Indigenous group said a planned expansion threatened sacred sites, including a 60,000 year old rock shelter.

The mining company asked the government to delay a decision on a heritage exemption request as part of a mine expansion, it said in a statement, which would allow it to damage sites of cultural significance to the Wintawari Guruma people.

The world's fourth biggest iron ore miner asked for a two-month halt to its request.

The Fortescue review comes as another major miner, Rio Tinto, faced a government enquiry earlier on Friday into how it legally blew up two rock shelters in May that had cultural and historical significance, including one showing 46 000 years of human habitation.

The Wintawari Guruma people, who have agreements with major miners for the use of their land in the iron ore rich Pilbara region, said they were unhappy with Fortescue's treatment of another sacred site and worried about the fate of other sites.

"Eastern Guruma people continue to mourn the irreparable damage inflicted on Spear Hill and many will no longer visit the area because it is distressing to see what has happened," they said, adding a culturally significant rock shelter there was now lying under a heavy duty haul road and close to a railway.

Fortescue's application relates to an area west of Spear Hill.

Initial testing on two rock shelters showed one dated back at least 60 000 years, the Wintawari Guruma said, while a third site contained petroglyphs - engraved rock art on a series of five stone panels – that depict animals figures and tracks, human figures and geometric motifs.

The Wintawari Guruma describe the art on the rocks as "sacred text" as they depict ancient Dreamtime narratives.

Fortescue declined to comment specifically on the preservation of Spear Hill but noted the firm had previously agreed a boundary around Spear Hill with the Wintawari Guruma, on which it had built its mine plan.

"As a result of this constructive consultation, we expect to achieve avoidance of significant cultural heritage beyond the current two-year mine plan," Fortescue said in the statement.

Fortescue has protected almost 6 000 Aboriginal cultural heritage places across its operations, it said.