Rio Tinto on Monday appointed former Anglo American group executive director Simon Thompson to lead the company, replacing their departing chairman who will step down next March.

Thompson, a veteran with more than 20 years industry experience, joined Rio as a non-executive board member in 2014. He will succeed Jan du Plessis, who will have served almost nine years in the role.

"The board is delighted to have appointed Simon to chair Rio Tinto," senior independent director Ann Godbehere said in a statement.

"He brings to the role a deep understanding of the mining industry, as well as a strong track record as a non-executive."

Thompson held a number of positions with Anglo American between 1995 and 2007, and previously worked in investment banking at S.G. Warburg and N M Rothschild.

He will take the reigns as the miner endures intense scrutiny from regulators.

Rio and two former top executives were charged with fraud by US authorities in October, accused of inflating the value of their Mozambique coal assets and failing to disclose mounting losses.

The world's second biggest miner has vowed to "vigorously" defend itself against the allegations.

The Anglo-Australian giant also announced in October it had settled a case with Britain's Financial Conduct Authority about the timing of writing down the same projects.

In August Rio reported a 93 percent jump in first-half net profit on the back of rising commodity prices and it returned a bumper US$3.0 billion to shareholders.

It announced in September a return of $2.5 billion to shareholders in a buyback after selling most of its Australian coal assets to China-backed Yancoal.